According to the police, the explosion on Wednesday at the Information Department shattered window panes and caused a wall to collapse.

  

"In the blast, nobody was killed nor injured," a police spokesman said.

  

The blast, which police believe was caused by the Maoists, followed a series of explosions in Kathmandu on Monday which left a schoolboy dead and 16 other people injured.

 

Ceasefire

  

Maoists have stepped up violence after they withdrew from a seven-month ceasefire in August and pulled out of peace talks because the government refused to set up a special assembly to redraft the constitution.

  

Army sources said the rebels also bombed a resort hotel belonging to former army chief Satchit Shumsher Jung Bahadur Rana in the western Gorkha district.

  

The rebels evicted occupants of the hotel before detonating three powerful bombs which seriously damaged the building on Tuesday, the sources said.

  

The rebels have been fighting for a communist republic in Nepal since 1996 and the insurgency has claimed more than 7800 lives.

 

The five-party alliance has been holding months of protests against the king for sacking the elected prime minister in October and postponing elections.

Meanwhile, around 1000 political activists were detained on Wednesday when Nepal's five main parties held a demonstration against King Gyanendra in defiance of a ban on public meetings.

 

Around 700 riot police were on guard as more than 6000 people gathered in central Kathmandu for the protest.

 

They rounded up around 1000 demonstrators, but did not have the manpower or enough vehicles to detain more, witnesses said.

  

It was the fifth demonstration by Nepal's major parties since the government on 1 September banned all gatherings of five people or more in the capital after Maoist rebels withdrew from a seven-month ceasefire.

  

The demonstrations have seen thousands of people detained but most of them released within hours.

  

The five-party alliance has been holding months of protests against the king for sacking the elected prime minister in October and postponing elections.