The Secret Service is heightening security around former President Donald Trump, an agency official said Monday, following the apparent attempt on his life just two months after an assassination attempt at a campaign rally.

“Given recent events, the Secret Service is taking a heightened posture in its protection of the former president,” the official said.

The new measures appeared to be visible Monday when Trump exited his plane in Pennsylvania and a Secret Service agent followed closely behind him.

The increased security comes on the heels of an incident at Trump’s golf course in West Palm Beach, Fla. Federal prosecutors recently charged Ryan Wesley Routh, 58, in connection with an apparent assassination attempt on the former president on Sept. 15.

Routh was charged with possession of a firearm by a convicted felon and possession of a firearm with an obliterated serial number. He appeared in a Florida court Monday and was ordered to be held pending trial.

court filing on Monday said that Routh, who was arrested on Sept. 15, dropped a letter off earlier this month that was addressed to “The World” and declared, “This was an assassination attempt on Donald Trump but I failed you.”

A U.S. Secret Service agent stands guard as former President Donald Trump, visits Sprankle’s Neighborhood Market, in Kittanning, Pa., on Monday.© Win McNamee

A civilian on Sept. 18 contacted law enforcement, saying Routh had dropped off a box at his residence containing the letter, four phones, ammunition and other notes, according to the filing.

The charges against Routh come a little more than two months after a gunman in Butler, Pennsylvania, shot the former president in the ear during a campaign rally in Butler, Pennsylvania, on July 13.

Trump now plans to return to Butler on Oct. 5 — one month before Election Day — according to three sources familiar with the campaign’s schedule.

The new security steps by the Secret Service also come after the House unanimously voted to boost protection for all presidential candidates. The bill would give candidates the same level of protection as presidents.

This article was originally published on NBCNews.com