BANGKOK - Thai authorities issued arrest warrants on Tuesday for three more suspects linked to bomb attacks as the capital hosted a diplomatic meeting last month, raising to seven the number of suspects still sought by police.

Six small bombs and six incendiary devices went off on Aug. 2 as the foreign ministers of Southeast Asian nations met in Bangkok, an event also attended by diplomats from China, the United States and other world powers.

Four people were wounded in the coordinated attacks police have linked either to political issues or a long-running insurgency in Thailand's Malay-Muslim dominated south.

Tuesday's warrants are for three suspects on charges of organized crime, arson, causing explosion and illegal possession of explosives, said deputy police spokesman Krisana Pattanacharoen.

"All the suspects are from the deep south," he said, referring to the region where an insurgency has killed 7,000 people since 2004.

Police last week issued warrants for four other suspects who remain at large despite a 100,000 baht reward for information leading to their arrests.

Authorities detained two men on Aug. 2 accused of planting fake bombs in front of Bangkok police headquarters before the coordinated attacks. The two have ties to the insurgency, police said, and were the subject of arrest warrants issued two weeks ago. -Reuters