A sewer worker died Tuesday after being washed away with four colleagues while repairing an underground sewage system in Toshima Ward as a thunderstorm lashed the Tokyo area, police and firefighters said.

The victim was identified as Hiroshi Oshima, 49, an employee of Hokuritsu Construction & Industry Co. who was supervising the work ordered by Toshima Ward, according to the Tokyo-based company.

Oshima was found unconscious about 3 km away in the Kanda River in Bunkyo Ward. He was later pronounced dead.

Six people were working on the aging pipe in a residential area 1 km east of JR Mejiro Station when a stream of water suddenly hit them.

One of the six managed to escape while the other five were swept away.

At night, firefighters found another body of a man at a pumping facility near the point where the workers were swept away. It was not immediately known if the body was one of the missing four: Akira Hamada, 29, Makoto Terai, 44, Ryuji Matsuo, 31, and Hiroaki Endo, 38.

Hokuritsu Construction is a subcontractor of Takenaka Civil Engineering & Construction Co.