June 22 (UPI) — Federal authorities have arrested two additional suspects allegedly involved in last week’s foiled attack targeting the Ultimate Fighting Championship bout at the White House, prosecutors said Monday.

Both suspects made their initial court appearances Monday, the Justice Department said in a release. Jordan Rincker, 28, of St. Joseph, Mo. appeared in a Kansas City court, and William Lee Spartacus Falkner appeared before a judge in Tacoma, Wash.

They each have been charged by criminal complaint with one count of conspiracy to commit murder.

Prosecutors said Falkner was arrested midday Friday, while Rincker was arrested Sunday.

A total of seven people have now been arrested and charged in a sprawling scheme that federal authorities have said involved 23 people conspiring to attack the White House’s Freedom 250 event on June 14, staged in celebration of the United States’ 250th anniversary and the birthday of President Donald Trump.

According to federal prosecutors, the alleged conspiracy planned to attack the north side of the event with explosive-carrying drones, which would force an evacuation to the south side of the event, where snipers would be deployed to open fire on the fleeing crowd, court documents state.

Authorities learned of the alleged attack from the parents of Tycen Proper, who alerted police to their son’s purchase of weapons and online activities. Proper, 19, was among the initial batch of five suspects arrested and charged last week.

The court documents state the group’s alleged grievances appear to be purported government corruption and involvement of U.S. lawyers with Israel.

FBI agents reviewing Proper’s communications were able to identify several alleged co-conspirators, including Falkner.

Prosectuors alleged that Falkner indicated in those communications that he had experience manufacturing and piloting drones and discussed loading them with explosives.

Online communications reproduced in the criminal complaint against Falkner allegedly show discussions on logistics of the attack, including potential flight costs, 3D printing and shipping of the drones.

“I can fly 40+ drones at the same time at the same target,” Falkner is alleged to have said.

Federal prosecutors alleged that just two days before the alleged attack, Rincker met Abraham Alvarez, 31, who was arrested and charged last week along with Proper, in person and accepted $1,200 from him. Rincker then allegedly sent a $100 CashApp payment from the money he received to another previously arrested and charged suspect, Bryan Roa, 24, to pay for his drive from California to Washington, D.C.

Authorities identified Rincker as an alleged member of the conspiracy through information they received from Alvarez following his arrest, according to court documents. Authorities also learned that Rincker allegedly gave a 12-gauge shotgun to Alvarez during an in-person meeting they had in Omaha.

The FBI executed search warrants for Rincker’s residence and storage unit, uncovering a trove of weapons and related paraphernalia, such as a gas mask with cartridge, night vision goggles, ballistic plates, a 3D printer and more.

No attack occurred at the UFC event, at which Trump and other members of his Cabinet were in attendance.

Asked about the thwarted attack a day after the event, Trump told reporters that he had heard about it.

“The attack that I watched were the fighters,” he said, to laughs.

“They were as good a fights as I’ve ever seen. The best.”