RICHMOND, Va. (WRIC) — Federal prosecutors say they should be able to use evidence found during the search of the home where two men accused by Richmond police of plotting a mass shooting were living because “officers had a reasonable concern for their safety” to conduct a sweep.

The argument from prosecutors comes in response to an effort from one of the men, Julio Alvarado Dubon, to suppress the evidence. In the Oct. 3 court filing, prosecutors also say that Dubon agreed to allow officers to search the home.

Dubon’s motion to dismiss the evidence claims Richmond police officers illegally searched his home in violation of his constitutional rights against unreasonable searches and seizures. Police said they seized multiple weapons and hundreds of rounds of ammunition from the home before arresting Dubon on a weapons charge.

“After telling the officers to ‘go ahead and check’ the residence for other individuals in the residence, the defendant never told the officers to leave, stop checking for other individuals, or otherwise protested the officers’ actions,” prosecutors in the U.S. District Court for the Eastern District of Virginia wrote in the motion.

Dubon was living in a home on Columbia Street when Richmond police conducted the search and seized two assault rifles, a semiautomatic pistol and about 200 rounds of ammunition. The other man identified by police in the alleged shooting plot, Rolman Balcarcel-Bavagas, lived with Dubon and was there when the search was underway.

Dubon’s court filing asserts he did not permit officers to search his home without a warrant, the search was not a “valid protective sweep” and there were no exigent circumstances to justify the search.

“Police entered the defendant’s residence for the stated purpose of having a conversation with him. Police then advised the defendant they would be walking through the residence to make sure no one else was present,” Dubon’s motion claims. “The defendant stated he believed the police needed a warrant to further enter the home. Police ignored this statement and continued to look through the home, without a warrant, consent, or exigency.”

Prosecutors acknowledge Dubon said that he understood that the officers “can’t get into my house without a warrant,” but claim that he “trailed off” and never protested when the detective searched the home.

Even if Dubon did not consent to the search, prosecutors argue that a “protective sweep” of the residence was warranted due to the circumstances of the case. The officers had a reason to believe they were in danger because they “were responding to a tip that someone from that home, namely one of the persons in the room with them, was planning a mass shooting,” and the ammunition and multiple magazines in the living room.

Richmond police said the department thwarted a mass shooting plot that targeted the city’s July 4 event at Dogwood Dell, with an investigation leading to the arrests of Dubon and Balcarcel-Bavagas.

Questions about the case continue after a city prosecutor contradicted Richmond Police Chief Gerald’s Smith claim that Dogwood Dell was the target and emails obtained through a public records request showed the chief was told a specific location was “unknown” before the July 6 press conference where he and Mayor Levar Stoney said the target was Dogwood Dell.

In August, Smith defended the department’s investigation and addressed the alleged plot in a one-on-one interview with 8News’ Olivia Jaquith. “I determined it was the Dogwood Dell from the facts; from the tipster; from the investigation; and from my 30 years of experience,” Smith said then.

City prosecutors dropped the initial charges against both men so federal prosecutors could pursue charges against them. Prosecutors in the U.S. District Court for the Eastern District of Virginia have not filed charges connected to an alleged mass shooting plot, but additional charges could come.

Dubon, a Guatemalan national, is charged with possession of a firearm by a person living in the U.S. illegally. A hearing on Dubon’s motion to suppress the evidence is set for Oct. 31, online court records show.