29th Reconnaissance Regiment

The Battle of Amtrup, better known as Operation: RELENTLESS STRIKE by the UNSC High Command and Operation Amtrup Guardians by the United Liberation Front, was a United Nations Space Command led battle against the United Liberation Front, Eridanus People's Republic, and Eridanus People's Militia in the city of Amtrup. Amtrup was known as the birthplace of the Eridanus II Insurrection and dissidence against the United Earth Government. The UNSC deployed the 15th Marine Division with support to capture Amtrup and establish a UNSC presence in the area.

Background
In 2491, the Colonial Military Administration's Department of Colonial Security released a Amtrup Threat Index detailing the growth of an Secessionist and Reformist movements. The DCS noted in their Index the movements were largely peaceful but needed to be addressed before the movements grew violent. Following the Far Isles Rebellion and the nuclear response from the UNSC in 2492, Amtrup and its neighboring area began advocating for breaking away from the United Earth Government and Colonial Administration Authority to govern themselves. Notably in 2494, Amtrup stoop up the Amtrup People's Liberation Militia to defend themselves from the CMA and UNSC. They utilizied propaganda and counterintelligence as their primary defense to harden their allies against the government and their incentives to back the UEG. Between 2494 and 2496, Amtrup intelligence agents infiltrated the DCS and began reporting false flag information about the safety of Amtrup to UNSC and CMA intelligence forces.

Amtrup commissioned the 2nd People's Army as a way to confuse UNSC intelligence and built up a 10,000 strong-force focused on infantry, unconventional warfare, intelligence, and other areas of warfare. The establishment of the Amtrup Anonymous Network as a homemade network allowed for the group to communicate and coordinate without the UNSC or CMA intercepting their messages. In 2502, Operation: KALEIDOSCOPE was launched and numerous leaders of the 2nd People's Army were targeted due to their activities across Eridanus II. Betweem 2502 and 2507, few leaders were assassinated and those who were killed, were used to portray the UNSC's ruthlessness against individuals freedoms and rights. Prior to 2513, Amtrup became a well-known for training Red Dawn Brigades and preparing them for urban warfare. They ran various counterintelligence operations, developed their cyberwarfare capabilities and perfected their defense of the city for when they got invaded. In the wake of the declaration of Operation: TREBUCHET, Amtrup mobilized the 2nd People's Army in preparation for battle and ran reconnaissance missions to build an understanding of the UNSC's plans.

Following the declaration of Operation: TREBUCHET, Joint Intelligence Operations Center - Eridanus system created the Amtrup Mission Desk to conduct initial intelligence assessments about the city. Using Reconnaissance Satellites, Ummanned Aerospace Vehicles, and other technical intelligence collecting equipment, the Mission Desk labelled Amtrup as an Area of Operational Capacity for the UNSC's Operational Capacity in the Theater Area of Operations. Between 2512 and 2513, the UNSC Marine Corps and Army debated who was going to establish the foothold in Amtrup. Both military branches leveraged their experience in other theaters until UNSC High Command settled on the UNSC Marine Corps due to their experience in the theater. When the Marine Corps worked closely with the Amtrup Mission Desk, they learned about the city's layout, the population, and what threats they were going to take on. Initial reports indicated a Low Threat Model to the city given its history during Operation: KALEIDOSCOPE.

Order of Battle
The UNSC Marine Corps was charged with the assault and occupation of Amtrup and selected the 15th Marine Division as the main spearhead force. Alongside the 15th Marine Division, numerous Reconnaissance, Engineering, Artillery, Aerospace, Intelligence, Surveillance, Reconnaissance and Shock Troops. The 15th Marine Air Wing worked alongside Aerospace Force's 194th Expeditionary Air Wing and Navy's Carrier Air Wing with aerospace dominance. The air component stood up the Combined Aerospace Component Command to serve as the primary Aerospace Operations Center and Command Control Center for all aerospace activity. Two battalions from the 105th Shock Troops Division split their operational control between the 15th Marine Division and Naval Special Warfare Joint Task Force - Eridanus System. Naval Special Warfare Unit Eridanus II added two squadrons of UNSC Navy Trident special warfare units.

The Amtrup 2nd People's Army was a UNSC Marine regiment-strength force with support from the Eridanus People's Militia at a battalion's strength. The aerospace components were severely lacking against the UNSC but proved to be powerful with an arsenal of unmmaned aerial vehicles from off-the-shelf vendors and homemade technology. The 2nd People's Army relied heavily on counter-insurgency and irregular warfare tactics to prolong the battle and deal a death-by-thousand-cuts to the UNSC. Notably, the 2nd People's Army Engineer Brigade developed the Amtrup Underground Network to help maneuver elements across the city to avoid UNSC reconnaissance platforms. The Eridanus People's Red Dawn Brigade provided counter irregular warfare tactics to deter the UNSC special warfare's capabilities. In addition to their force and capabilities, their counterintelligence forces proved to be extremely effective in hiding their true force to the UNSC and its allies.

April
"Operation: RELENTLESS STRIKE was a textbook failure of on-the-ground intelligence and an over-reliance of overhead technical intelligence. Amtrup's forces concealed their full force package from the UNSC and prepared for the invasion. UNSC intelligence enterprises conducted numerous assessments that checked the strategic importance of the city but failed to realize the scope of the forces waiting for the UNSC. How the UNSC Marine Corps adapted to Amtrup was through fearless leadership and evolving a fighting force on the fly."

- Lieutenant Colonel First Last's research paper introduction from the UNSC Naval War College - Reach, 2523.

As the UNSC Navy's 32nd Fleet dispatched Task Force 32-2 and 32-5, the UNSC Marine Corps prepared for their occupation of Amtrup. The assigned UNSC Navy Task Forces included a Quick Reaction Force from the 105th Shock Troops Division, support elements from the 15th Marine Expeditionary Force, and the Marine Air-to-Ground Assault Force to support Marine Air-to-Ground Task Force operations. Aerial Intelligence divided Amtrup into 27 Districts of Operations to help with building an organized intelligence pipeline to not confuse reports with different areas. Upon the 15th Marine Division's arrival in April 9th, they encountered minimal resistance from the Amtrup 2nd People's Army. The 2nd People's Army was alerted of the 15th Marine Division's movements and prepared the city for battle. Evacuation of civilians who did not want to be involved in the fighting were moved through the underground network while the remaining civilians created the Amtrup Civilian Battalion to act as double agents for the 2nd People's Army.

3rd Battalion/43rd Marine Regiment engaged the 2nd People's Army first on April 11th during a night-time presence patrol in DoO 06. Once the first firefight broke out, the 2nd People's Army engaged the patrols from their fortified positions and utilized their crossfires to cut down squads before they could react. Marine Command and Control began reinforcing the battle lines the 2nd People's Army started as they Army maneuvered through their underground network to throw the Marines off. Throughout the week, DoO 6, 7, 10, 14, 16, 21, 22, 23, and 31 became the main focus for the Marine Corps. Artillery and Close Air Support became useless given the Marine's inability to triangulate the enemy with their targeting technology. Whenever the Marines did conduct an airstrike, civilians from the Amtrup Civilian Battalion came out screaming for them to stop since they were bombing innocents. Those civilians were brought behind the Marine lines and taken care of, while feeding vital information to the underground forces nearby.