There were more arrests and increased violence in Zimbabwe as a general strike went into a second day. Bombs were detonated at two supermarkets.

Police spokesman Wayne Bvudzijena says home-made bombs damaged two supermarkets in the small town of Kadoma, about 100 kilometers southwest of Harare. In addition, he said an explosion superficially damaged a bridge across a river near Kadoma.

In other violence, at least two commuter buses were set on fire in a suburb east of Harare.

Police say that less than 200 people have been arrested for activity related to the strike, but other sources say the figure is close to 400 and includes two opposition members of parliament.

The strike has spread to virtually every shop and factory in Zimbabwe's two largest cities, Harare and Bulawayo.

The government has not made any substantial statement about the strike, which was called by the opposition Movement for Democratic Change to protest the political and humanitarian situation in Zimbabwe.

A spokesman for the opposition, Paul Themba Nyathi, blamed the violence accompanying the strike on agent provocateurs.

The situation at various police stations around Harare is chaotic, with scores of detainees milling around corridors. Police at Harare Central Police Station said they did not have full lists of those in custody.

The strike is the largest and most successful challenge to President Mugabe since his controversial re-election last year.

Strikes are illegal in Zimbabwe, but the Movement for Democratic Change says it will be continuing mass action in the days ahead.