Latvia's president Andris Berzins has said a supermarket cave-in that claimed at least 52 lives should be viewed as a murder case.
In comments aired by public broadcaster LTV on Saturday, Berzins said: "This case must be treated as the murder of many unprotected people," adding that Thursday's disaster in the capital Riga should be "investigated at maximum speed".
Latvians on Saturday began three days of official mourning for the victims of Europe's third worst roof disaster in the past 30 years. It happened after a roof caved in on shoppers in a busy Riga supermarket.
In Afghanistan, you're prepared for death every day, but not when you are here at home.
Rescuers in the small Baltic EU state have continued combing the rubble for survivors.
Nils Usakovs, the mayor of Riga, said five people were still feared trapped inside the Maxima supermarket.
"This has been a hard day for all of Latvia," Prime Minister Valdis Dombrovskis said late on Friday on public television of the catastrophe that shook the nation of two million.
Three firefighters among the 200 rescuers who rushed to the scene were among those killed, while other rescue workers got trapped inside during a second collapse.
"In Afghanistan you're prepared for death every day, but not when you are here at home," Afghan veteran Maris Utinans told the AFP news agency while working on the rescue effort late on Friday.
Moment of silence
Latvia will also observe a moment of silence on Monday for the catastrophe, its deadliest since independence from the Soviet Union in 1991, while police probe what caused the cave-in at the two-year-old supermarket.
Previous major roof accidents in Europe happened in 2006, the first killing 66 people when a Moscow market roof collapsed while a second claimed 65 people in Chorzow, southern Poland, when a snow-laden roof caved in on an exposition hall.
Mourners at the disaster site late on Friday lay heaps of flowers and lit candles around the metal police barricades as volunteers handed out hot drinks to them and to rescue workers.
"It is a terrible tragedy for the city and the whole country. My friends and I just wanted to pay our respects by coming here to light a candle and lay flowers," Janis Berzins, 24-year-old Riga resident, told AFP.
Speculation about the possible cause of the cave-in has centred on plans to build a rooftop garden on the building.
A photograph published by Latvia's Diena daily on Friday showed an aerial view of the roof prior to the collapse, covered in a garden with soil, shrubbery and a children's play gym.
Visiting the scene, Prime Minister Dombrovskis said police had launched a criminal investigation to find the cause of the disaster.
Run by the Lithuanian-owned Maxima chain - Latvia's number two retailer after Rimi - the supermarket was built in 2011 and was named one of the country's top three architecture projects that year.
Local council official Juris Radzevics said that plans had been submitted to the council to turn the roof into a green area.