Bangkok, Mar 14 (IANS): At least eight people were killed and seven others injured after fire suppression chemicals were accidentally released at a bank in Thailand's capital Bangkok, the media reported on Monday.

The accident at the Siam Commercial Bank (SCB) Head Office occurred at 9.30 p.m. on Sunday when smoke from the basement prompted the fire extinguishing system of the building to release the gas pyrogens, or flame retardant, killing eight people on the spot when the chemicals "sucked all oxygen from the building", the Bangkok Post reported.

Firemen said when they finally began breaking into the bank building, they found tightly locked doors by bank-grade security.

They managed to rescue three people on the ground floor but could not access either the basement or first floor.

According to an official statement by SCB, this was "an accident caused by the negligence of the contractor hired to improve fire protection of the building".

However, it gave no further details.

The bank issued a press release late Sunday night, saying there was no fire or explosion, so all banking offices would be open on Monday as usual.