Two people were found dead early Sunday following a house fire in Katsushika Ward, Tokyo, that left four other residents injured, police and firefighters said.

The fire broke out around 3:50 a.m. and destroyed the two-story wooden house.

The two bodies were believed to be those of Tomiko Usami, 70, wife of the home's owner, Masaru Usami, 68, and their daughter, Naomi Washimi, 39.

Washimi's older daughter, 15, suffered serious injuries, including a broken bone, while her younger daughter, 13, son, 12, and Masaru Usami sustained minor injuries, including facial burns.

The cause of the fire was under investigation.

The six people lived together in the house, which had a total floor space of about 100 sq. meters. The Usamis and the son slept on the ground floor, and Washimi and the two daughters upstairs.