Police tightened security around Burma's (also known as Myanmar) detained opposition leader Aung San Suu Kyi on Thursday after an American man was arrested for allegedly swimming across a lake and sneaking into her lakeside home.

The Myanma Ahlin newspaper reported that authorities fished the man out of Rangoon's Inya Lake early Wednesday while he was returning from the visit to Suu Kyi's home. The report identified the man as John William Yeattaw but gave no details of his motives.

It would be the first time anyone has sneaked into Suu Kyi's compound or swam across the lake in an attempt to get there.

Dozens of police entered Suu Kyi's compound Thursday morning and stayed until late afternoon, according to neighbors who spoke on condition of anonymity for fear of reprisals in the military-ruled country. It was not clear what the police were doing there.

Despite police checkpoints and barbed-wire barricades outside the home, police rarely enter Suu Kyi's compound, where she has been kept under house arrest for more than 13 of the past 19 years.

The newspaper report said the American man had confessed to swimming across the lake Sunday evening, sneaking into Suu Kyi's residence and then swimming back late Tuesday before being spotted by police and arrested early Wednesday.

"He secretly entered the house and stayed there," the newspaper reported, saying that he swam with an empty 5-liter plastic water jug, presumably to use as a float. "Further investigation is under way to find out his motive for secretly entering the restricted area."

Police confiscated the man's belongings, which included a U.S. passport, a black backpack, a pair of pliers, a camera and two U.S. 100 dollar bills, the newspaper reported.

A spokesman from the U.S. Embassy in Rangoon said consular officers were "seeking access" to the man as is routine in any case of an American citizen arrested overseas.

"Right now we don't know anything more than what is generally known, that this man was arrested for swimming across the lake and wound up being at Aung San Suu Kyi's house," said spokesman Richard Mei, who said he could not immediately confirm the man's identity or spelling of his name.

By the end of the day Thursday, Mei said there was "no response from police with regards to our request to see him."

Suu Kyi's home is tightly guarded and she is not allowed visitors, aside from her doctor. Swimming in Inya Lake in the vicinity of Suu Kyi's compound is not allowed.

It was unclear whether Suu Kyi herself had any contact with the unauthorized visitor. Nyan Win, spokesman for her National League for Democracy party, said he had no information about the American visitor aside from what he had read in the state-controlled newspaper. But he said it was worrisome how easily the man accessed the tightly guarded home.

"We are very much concerned of Daw Aung San Suu Kyi's security. What happened shows a security lapse," Nyan Win said. "Daw" is a term of respect in Burma.

Suu Kyi has been held without trial for leading an internationally hailed movement for democracy in Burma, which has been ruled by the military with an iron fist since 1962.

Her party won Burma's last elections in 1990, a result the military junta never recognized.

Earlier this week, the junta rejected an appeal to free Suu Kyi, whose most recent period of detention is due to expire May 27, according to the party spokesman.