Maldives police patrol the streets of the capital Male. Maldives Vice President Ahmed Adeeb was arrested Saturday over last month's alleged attempt to assassinate President Abdulla Yameen. 

AFP/Male

Maldives President Abdulla Yameen on Sunday described his deputy as a threat to national security after his arrest over an alleged attempt to assassinate Yameen in a speedboat bombing last month.

Soldiers and police patrolled the capital Male's streets in stepped up security, one day after vice president Ahmed Adeeb was arrested as he arrived back in the honeymoon islands from an official trip abroad.

"The vice president is being detained for the safety and security of the entire nation," Yameen said in a nationally televised address.

The president was unhurt in the September 28 blast on his boat, which authorities described as an assassination attempt. The explosion left his wife and two others slightly injured.

Yameen also claimed bomb-making equipment had been discovered during raids on the homes of Adeeb's associates in the capital on Saturday.

"During raids on close associates of Adeeb, police found bomb-making material," the president said. "There are many allegations concerning the vice president," he added.

The comments came as a court ordered Adeeb detained for 15 days to give police more time for investigations. The government said on Saturday that Adeeb would be charged with "high treason".

The Maldives is a popular upmarket tourist destination, but its image has suffered in recent years due to prolonged political unrest.

Crackdown on dissent  

The country has come in for tough international criticism over the jailing of its first democratically elected leader Mohamed Nasheed, after a rushed trial that the UN said was seriously flawed.

Yameen, who came to power in November 2013 following a highly controversial election, jailed Nasheed for 13 years in March on terror-related charges and faces international censure over his crackdown on dissent.

Supporters of Nasheed, the main opposition leader, have maintained that the conviction was part of a strategy by Yameen's regime to silence him.

Hours before Adeeb's arrest, the president sacked his police chief, the latest in a series of firings seen by some as a purge of individuals whose loyalties may be in doubt.

Defence Minister Moosa Ali Jaleel was sacked 10 days ago, while on Thursday Yameen also fired his main government spokesman Mohamed Shareef, a minister in his cabinet.

In his address, Yameen also accused Adeeb of trying to destroy evidence and blocking the investigation into the blast, without giving details.

He said Adeeb needed to be removed from his post because of alleged and unspecified influence over police.

"Because of his influence over the police, it was deemed that an impartial investigation could not be carried out with the vice president remaining in office."

Adeeb was unceremoniously escorted away by police as he disembarked from a Singapore Airlines flight on Saturday, with a coastguard boat taking him to the nearby prison island of Dhoonidhoo.

Yameen appointed Adeeb as his deputy three months ago after impeaching his original running mate Mohamed Jameel on charges of treason.

He had changed the Maldives' constitution to reduce the permissible age of a vice president from 35 to 30 so that Adeeb could be given the job.

Adeeb, who had a meteoric rise in politics, was also a hate figure for the country's main opposition, which accused him of sending underworld gangs to launch attacks against dissidents.