(CNN)A 26-year-old man accused of targeting homeless men in a Las Vegas shooting spree has been arrested, the city's police said.
Suspect arrested in killings of homeless men in Las Vegas
Joshua Castellon was taken into custody last week on a federal weapons charge. He was charged on Monday with two counts of murder and two counts of attempted murder in connection with the shootings, police said.
One of the victims was shot while sleeping under a Las Vegas freeway and another victim was shot and killed while sleeping outside a business, police said.
"These were horrible crimes made worst by the helplessness of the victims," said Cpt. Robert Plummer with the Las Vegas Metropolitan Police Department.
CNN has not been able to determine if Castellon has an attorney.
In a span of nearly seven hours, three men were shot January 29.
The first shooting occurred at 12:30 a.m. when a man was shot outside of a convenience store in Logandale. The man survived, Plummer said.
Then, at 3:06 a.m., Brian Clegg was fatally shot while sleeping outside of a business on a busy street in Las Vegas. That was followed by another shooting in Las Vegas at 7:13 a.m., where a man woke up with a gunshot wound to the head. He survived, Plummer said.
Four days later, James Edgar Lewis was found dead under a Las Vegas freeway, police said.
Video footage showed a man wearing a dark top emerging from a dark-colored SUV and shooting Lewis twice in the head before fleeing.
There was no struggle, no fight.
"It's basically an execution," Lt. Dan McGrath of Las Vegas Metropolitan Police had said.
Police first approached Castellon and interviewed him on February 8 after they found him sleeping in a vehicle that matched the description of the one spotted during the shootings, according to the federal complaint.
Days later, detectives spoke with Castellon's estranged wife who said she believed he had bought a revolver. She also told police she confronted her husband and asked him if he was the shooter after seeing surveillance videos from the scenes that had been made public but he denied it, the document states.
After police spoke with Castellon again, officials with the Bureau of Alcohol, Tobacco, Firearms and Explosives arrested him on a federal weapons charge. His arrest came after he told police that he bought the revolver to resell it to a "friend of a friend," the complaint indicates.
He did not indicate his intentions to sell the firearm when he bought it, which made it an illegal purchase.
The weapon has not been found, CNN affiliate KSNV reported.