RIYADH, April 13 (Xinhua) -- A residential building used as a labor camp in Riyadh caught fire on Friday, killing seven and injuring eight others, Sabq local online news reported.

The fire broke out at the entrance of the building which has no other exists, said Maj. Mohammed Al Hamadi, spokesman of the civil defense in the capital.

Smoke inhalation is the main cause of death and injury, he added.

According to the spokesman, 45 out of the 54 expatriate workers living in the two-storey building were inside it during the fire.

An investigation has been launched to look into the cause of the fire, he said.

Deadly fires in the labor camps are common in the neighborhood as low-paid expatriates tend to live in these old buildings lacking safety measures to save most of their wages.