Riga - Four people were killed and around 30 others injured on Thursday when the roof of a supermarket collapsed in a suburb of Latvia's capital Riga, emergency services said.
"There are four victims... rescue efforts will continue through the night but it's too early to name a cause or say whether there will be more victims or survivors," emergency services spokeswoman Viktorija Sembele told AFP.
A firefighter working at the scene was among the dead, she said, but she was not able to immediately provide information about the age or sex of other victims.
Riga's deputy mayor Andris Ameriks told the local BNS news agency the disaster could have been caused by a blast, but did not elaborate.
Run by the Lithuanian-owned Maxima chain - Latvia's number two retailer after Rimi - the supermarket was built in 2011, according to local media reports, which also said it had recently been under renovation.
Mayor Nils Usakovs announced he was cancelling his leave and calling an emergency meeting of municipal and rescue services for Friday.
"As soon as rescue work has finished, construction experts will investigate the causes," said a press release from his office.
Up to 13 emergency brigades and 17 ambulance teams were working at the site late on Thursday.