Banjul - Gunfire erupted around the presidential palace in Gambia's capital Banjul overnight and soldiers blocked a bridge leading to the centre of town but the government denied reports of an attempted coup.A diplomat said unknown gunmen had attacked State House during the night but shooting had died down later. Local diplomats and media said President Yahya Jammeh was abroad, either in France or Dubai, when the violence broke out.Jammeh, 49, who himself came to power in a coup 20 years ago, has stifled dissent in the tiny and impoverished West African nation and has faced increased criticism from abroad over issues ranging from human rights to claims he can cure Aids.Callers on foreign-based opposition online radio stations urged residents to rise up and prevent Jammeh from returning.A senior West African diplomat told Reuters that mutineers were in control of some strategic pockets of the capital on Tuesday afternoon.State radio mostly played traditional music but an announcer read a government statement playing down the incident. "Contrary to rumours being circulated, peace and calm continue to prevail in The Gambia. [The] government would like to urge the public and all businesses to continue with their normal activities," it said.Gambia, a splinter of land wedged inside Senegal, has ocean beaches that attract large numbers of tourists, particularly during the northern hemisphere winter. They include about 60 000 Britons a year and the British foreign office advised citizens to stay indoors and avoid public gatherings.Eyewitnesses in the centre of Banjul, which is cut off from the rest of town by the Denton Bridge, said security forces were positioned on street corners and patrolled after the several hours of shooting in the early hours of Tuesday morning.Aids cureBanks and other offices in the coastal capital and surrounding neighbourhoods remained closed and residents locked themselves indoors.A French foreign ministry spokesperson said Jammeh was not on an official trip in Paris and diplomatic sources said there was no indication that he was in France on a private visit either.Gambian state television said at the weekend that Jammeh had travelled to Dubai. But there was no official confirmation of where he was on Tuesday.Earlier this year, the European Union withdrew millions of dollars in aid, shortly after Jammeh signed into law an act that could imprison homosexuals for life. In 2012, he was criticised for executing nine people being held in prison.Jammeh has long claimed to have discovered a natural remedy to Aids, provoking criticism from medical experts.In recent years, he has frequently reshuffled senior military and civilian officials, a policy that has prevented potential rivals accruing power, but has stoked instability.