It took Ground Self-Defense Force officials about two hours to defuse the unexploded bomb in Chofu, western Tokyo, Japan's Kyodo news agency reported Sunday.

Chofu authorities then declared the city safe and allowed residents to return to their homes.

People living within 550 yards of the bomb were ordered to leave the area and trains going to and from Chofu and Tsutsujigaoka were temporarily shut down.

Officials said the explosive device, discovered in March, was likely a 1-ton bomb released from a U.S. B-29 bomber that crashed in 1945.