Bangkok, Aug 21 (IANS): Thai police have launched a search operation for a "woman wearing a black shirt" over the deadly bombing of a shrine in capital Bangkok, a media report said on Friday.

"I would urge her to come forward to provide information to police," Lt. General Prawut Thavornsiri, spokesperson of the Royal Thai Police, said.

However, no further details have been provided about the woman as of now, CNN reported.

On Thursday, two men captured on surveillance video entering the shrine ahead of Monday's bombing that killed 20 people and injured 125 others, turned themselves in, but it does not appear they were linked to the attack, Prawut said.

Meanwhile, police have singled out one main suspect, describing him as an unidentified foreigner who was caught on surveillance video hiding a backpack under a bench at the shrine minutes before the bomb detonated.

Royal Thai Police Commissioner General Somyot Poompanmoung said that he believed that "several teams" were involved in the preparation and execution of the attack.

"This operation was carried out by a big network," he said.

Thai security forces are sharing information with Interpol, the global police organization, and with intelligence agencies from allied countries, officials added.