A fire broke out at a three-story department store in the southern Philippines on early Wednesday, killing seventeen employees who were sleeping there, officials said. The store was not open when it happened.

The fire broke out at around 4 a.m. local time at a commercial building on Montilla Boulevard in downtown Butuan City, which is located in the southern province of Agusan del Norte. Twenty female employees were sleeping in one of the stores overnight, which is a common practice in the Philippines.

The victims, who were sleeping on the top floor, woke up when the building was already filled with smoke, making it difficult for them to find a way out. Three people were able to escape the building with no serious injuries, and firefighters later recovered the badly burnt bodies of the seventeen victims.

It took firefighters some five hours to put out the fire in the commercial building, which had been leased to businesses such as Novo Jeans, Globe, Smart, Western Union and St. Peter. The building had previously also been used as a popular theater house.

The head of the Caraga Regional Police, Chief Superintendent Reynaldo Rafael, told the Manila Bulletin that preliminary investigations indicated that the blaze began in the Novo Jeans outlet and quikcly spread.