Unfinished and abandoned tower blocks in Los Angeles that have become a destination for vandals, graffiti artists and BASE jumping thrill-seekers have cost 3,000 hours of police time so far, authorities said Tuesday.

LAPD Chief Michael Moore told a news conference Tuesday that the Oceanview Plaza Towers in a busy downtown area of the city had "strained our deployment," NBC News reports.

"We have called in some officers on an overtime basis, so that we can provide for these added patrols or station them at that site to deter vandals and others from gaining access to it while also ensuring that we meet the minimum deployment requirements for stations across the city," he said.

He was speaking after footage went viral of a man parachuting from the top of one of the towers on Monday, prompting an urgent safety warning from city mayor Karen Bass.

The towers began construction in 2015, but by 2018 money had ran out and building work stopped in 2019 after the China-based developer went out of business, NBC 4 LA reported.