Bangkok, Thailand (CNN) -- At least 11 construction workers were killed Tuesday when a big cement beam fell on them in a Bangkok suburb, at the site where they were working, Thai police said.
About 27 workers were on their lunch break -- some of them eating, others just resting -- in the district of Bangpli when the beam fell on them, said police Lt. Col. Somchai Piakhan.
More than a dozen injured people have been transported to nearby hospitals, and at least one worker is still trapped inside the rubble, police said.
A rescue team is trying to lift the wreckage of cement and steel to free anybody trapped underneath, authorities said. Sniffer dogs have also been deployed to find possible survivors.
The collapse took place around noon at the construction site of a new hospital.
Bangpli is southeast of Bangkok, in Samut Prakarn province.
CNN's Kocha Olarn reported from Bangkok, and Jethro Mullen wrote from Hong Kong.