The ousted president of the Maldives, credited with bringing democracy to the Indian Ocean islands, said on Wednesday he had been forced out of power at gunpoint, prompting clashes between police and angry supporters.

Mohamed Nasheed, who in 2008 became the first democratically elected president of the 1,200-island archipelago best known for luxury tourism, resigned on Tuesday after three weeks of opposition protests culminated in a police revolt.

Just a day after he stepped down, it was as if Nasheed had stepped back in time: riot police and soldiers launched tear gas grenades and beat him and other supporters, a scene played out scores of times under the 30-year rule of former president Maumoon Abdul Gayoom, whom he succeeded.

Witnesses said around 40 or 50 people including Nasheed had been injured, some severely. Police and soldiers surrounded the main hospital and kept journalists out of Republic Square, the site of the protest on Male's northern seafront.

"I was quite close to him when they began to charge. He had some cuts and bruises but he was beaten quite badly," a cousin of Nasheed, who asked not be identified, told Reuters.

Adam Manik, a senior official in Nasheed's Maldivian Democratic Party (MDP), said the former leader was in a safe house. The party in a statement appealed for international help, and Nasheed blamed his old rival Gayoom for the crisis.

AT GUNPOINT
Nasheed on January 16 ordered the military to arrest the criminal court chief justice, saying he was blocking multi-million dollar corruption and human rights cases against Gayoom allies. That set off the protests that led to his departure.

"Yes, I was forced to resign at gunpoint," Nasheed told reporters after addressing a meeting of his Maldivian Democratic Party (MDP) in his first public appearance since his ouster. "There were guns all around me and they told me they wouldn't hesitate to use them if I didn't resign."

Earlier, a close aide told Reuters the military on Tuesday marched Nasheed into his own office to give his resignation on state TV, in the first eyewitness account.

"The gates of the president's office swung open and in came these unmarked vehicles we've never seen before and Nasheed came out with around 50 soldiers around him, and senior military men we'd never seen before," said Paul Roberts, Nasheed's communications adviser.

Nasheed in his resignation broadcast said he was stepping down to avoid bloodshed against the people.

Vice President Mohamed Waheed Hassan Manik was installed as president, and on Wednesday promptly denied being part of any coup despite a widely reported January 31 meeting at which opposition parties swore allegiance to him.

"Do I look like someone who will bring about a coup d'etat?" Waheed told a news conference. "There was no plan. I was not prepared at all."

In Washington, the U.S. State Department said it was sending its top diplomat for the region, Assistant Secretary of State Bob Blake, to Male on Saturday but said it did not regard Nasheed's ouster as unconstitutional.

"Our view as of yesterday, and I don't think that that has changed - obviously we will collect more information going forward - was that this was handled constitutionally," State Department spokeswoman Victoria Nuland told reporters.

She said the United States was concerned about the violence, was calling for calm and urging the government and political parties 'to work together to resolve the situation peacefully'.

'ACT OF TERRORISM'
Waheed, who runs a small party, said he expected to form a cabinet in a few days, and had invited all parties to join a national unity government that would rule until presidential elections in October 2013.

Nasheed's party refused, and he urged Waheed to step down.

"I call on the chief justice to look into the matter of who was behind this coup. We will try our best to bring back the lawful government," Nasheed told a gathering of the MDP party faithful in a conference call on Wednesday.

As soon as the meeting broke, Nasheed led thousands of supporters across the capital to Republic Square, scene of many of the Maldives' political turning points including the police mutiny on Tuesday.

There, police and soldiers in riot gear began firing tear gas and charged protesters with batons, beating some and hauling away others. The Maldivian police, on state TV, termed the march and ensuing protest 'an act of terrorism'.

There were unconfirmed reports that Nasheed supporters attacked two police stations on the second-largest atoll, Addu.

Several ambulances raced away from the scene and dozens of sandals lay strewn and broken across the pavement, abandoned as people took flight from the police charges.

The political tumult in the Sunni Muslim nation was far from the tourists who stream to the chain of desert islands, seeking sun and sand at luxury resorts that can cost $1,000 a night.

Nonetheless, the British government advised its citizens against travel to Male.