SHANGHAI, Aug. 1 -- A 28-YEAR-OLD man who climbed the 88-floor Jin Mao Tower last night will be held in custody for seven days, the Shanghai Public Security Bureau announced today.

The Hunan Province native surnamed Zou will be held for disturbing social order at a public venue.

No motive was given for the man's ascent.

City police received an alert at 6:40pm yesterday about a man climbing the tower.

``Police and firefighters were dispatched to the scene," said Yang Ye, a security bureau official. "Police set up a security perimeter around the building and dispersed onlookers. Some officers tried to persuade the man to quit the climb from the building's interior and closely monitored his movement. A huge air cushion was inflated in case the man fell.''

Many people gathered to watch Zou's climb, causing traffic congestion in the area and drivers had to change their routes, Yang said.

The man in a black T-shirt and white trousers started the ascent from the top of a dumpster and reached the 88th floor about 9pm. An earlier report said he finished the climb around 11pm. However, Yang clarified today that Zou refused to come inside for nearly three hours after reaching the top before police experts persuaded him to leave the dangerous spot. Zou was promptly pulled into the building and arrested.

Zou is the sixth person to ascend the 421-meter Jin Mao Tower, the fourth tallest building in the world, without permission. Frenchman Alain Robert, dressed in a Spider-Man costume, climbed and descended the tower on May 31. He was detained for five days.