Solomon Islands police were out in force on the streets of the capital Honiara on Monday after rioting among the victims of recent devastating floods, authorities said.

Deputy Police Commissioner Juanita Matanga called for calm and advised citizens to stay at home amid fears of renewed violence in the impoverished city.

Matanga said the rioting on Friday and Saturday nights, which left several shops burned out, would not be tolerated and police were ready to quell any further disturbances.

"It's everyone's responsibility to stop anything or anyone causing trouble in our country as we will all suffer," she said.

The UN Office for the Coordination of Humanitarian Affairs (OCHA) said the rioting was sparked by dissatisfaction over aid distribution following floods last month that killed 22 people and left thousands homeless.

According to the Australian Broadcasting Corporation, 4,500 people remain in evacuation centres, cases of diarrhoea are high and thousands do not have adequate access to drinking water.

Prime Minister Gordon Darcy Lilo's spokesman, Robert Iroga, said unemployed youths were also to blame.

"We believe basically what happened over the weekend was criminal opportunists breaking into public utilities or private shops as they have in the past," Iroga told Australian broadcaster SBS.

Honiara-based journalist Dorothy Wickham said Chinese-owned businesses were targeted by the mob of about 400 people and most Chinese shops in the capital had closed in case trouble flared again.

The Chinese were also the focus of rioters when disturbances destroyed large parts of downtown Honiara in 2006, with an official report lambasting police for failing to stop looting and burning.

However, Wickham said that in the latest disturbances, squads of riot police trained by Australian peacekeepers managed to contain the violence before it escalated out of control.

An Australian-led peacekeeping force was sent to the Solomons in 2003 to end five years of civil strife and only finished its mission last year.