The suspect in the Trump assassination attempt is said to have been in hiding for almost 12 hours

The man accused in connection with an assassination attempt on former President Donald Trump is said to have been in hiding for nearly 12 hours before fleeing when a Secret Service agent shot him.

Trump was unharmed in the incident, which occurred on Sunday, Sept. 15, at Trump National Golf Club in West Palm Beach, Florida. Ryan Routh, 58, has been charged with possession of a firearm by a convicted felon and possession and receipt of a firearm with an obliterated serial number in connection with the incident, the Justice Department said.

According to a criminal complaint obtained by PEOPLE, cellphone data indicates that Routh was outside from 1:59 a.m. Sunday until 1:31 p.m., the same time he was approached by a Secret Service agent.

The incident occurred when the agent was walking the golf course while the former president was golfing and allegedly spotted a rifle sticking out of a line of trees. The agent then fired shots at the rifle, the complaint states.

Authorities say a witness then saw Routh flee the tree line, get into an SUV and speed away.

Routh was arrested after Martin County Sheriff's Office officers conducted a traffic stop, the complaint states.

At the tree line where the first encounter occurred, authorities found a scoped rifle, a digital camera, two bags, a backpack and a plastic bag of food, the complaint said.

Routh made his initial court appearance on Monday, Sept. 16, and a detention hearing is scheduled for Sept. 23, prosecutors said.

The authorities have not yet announced a possible motive.

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Routh, a former North Carolina resident, is a convicted felon. In addition to more recent convictions for possession of stolen goods, North Carolina criminal records show that Routh was convicted of possession of a weapon of mass destruction in 2002.

The News & Record reported at the time that Routh had barricaded himself with a rifle after a standoff with police.

The incident at Trump's golf club is the second time in recent months that the former president has been the target of an assassination attempt. In July, a man fired several shots during a campaign rally in western Pennsylvania. One person was killed.

Trump suffered a bloody ear in the incident but was otherwise unharmed.