Two men ended up in San Francisco County Jail Sunday, after they climbed a 525-foot tower on the eastern span of the Bay Bridge.

According to a spokesperson with the California Highway Patrol, calls started rolling in at around 3 p.m. Sunday, all reporting two guys clambering up a cable that passes the bike path on the southern side of the bridge, then rises all the way to the tower's tip.

"What happened was they came up the path, and between the path and a cable that runs up to the top, there is a railing," CHP spokesperson Officer Vu Williams told the Bay Area News Group.

"They jumped over the railing and made it up the cable."

The duo, identified by Bay City News as Danil Grigoriev, 18, and Robert Canales, 23, are believed to have made it to the top of the tower. "By the time we got there, we saw them coming back and we arrested them when they came back down," Williams told BANG.

Though the CHP had initially requested Coast Guard assistance, "no other agencies' help was required," BANG reports.

“They were just walking back down the cable the same way they came up,” Williams said to the Chron.

The duo were in police custody by 3:30, according to the CHP, and were booked into SF County Jail on suspicion of unlawful access at a vehicular crossing, general trespassing and public nuisance. Grigoriev was also tagged onsuspicion of resisting arrest, Canales for "aiding and abetting," BCN reports.

As of yet, the CHP has not said why the men climbed the tower, but whatever the reason, it's not OK, Williams says.

“We ask that people, for their own safety as well as the safety of the motorists, stay on designated paths,” he told the Chron. “It’s a safety issue for all involved.”