World Bulletin/News Desk
Tokyo Electric Power Co said it was the first time a labourer had died as a direct result of an accident inside the plant since the nuclear disaster in March 2011, the world's worst since Chernobyl in 1986.
An earthquake and tsunami struck the plant, 220 km (130 miles) northeast of Tokyo, sparking triple nuclear meltdowns, forcing more than 160,000 residents to flee from nearby towns and contaminating water, food and air.
"In the three years since the disaster, we had not had any worker deaths caused by work (inside the plant). The fact that such a serious accident has occurred is deeply regrettable," said Tepco spokesman Masayuki Ono.
The utility will suspend cleanup operations for an immediate safety inspection, Kyodo newswire reported.
Most workers inside the plant are contract labourers hired by multiple layers of construction companies. A Reuters investigation last year found widespread labour abuses, where workers said their pay was skimmed and there was little scrutiny over working conditions inside the plant.
Tepco on Friday would not name the worker's direct employer, but said he reported up to Toso Fudosan Kanri Company, a first-tier contractor under Tepco. The worker was in his 50s, the utility said.
The company confirmed it had hired the worker through another subcontractor.
Tepco has been widely criticised for its handling of the cleanup. The operator was plagued by a series of leaks of radioactive water from hastily built tanks at the site last year and it has repeatedly promised to improve working conditions.
Earlier on Friday, Tepco said work to remove fuel rods from one of the destroyed reactor buildings had been halted after a worker had mishandled a giant crane, the first major delay in an operation to remove 1,533 fuel rod assemblies.
The worker started moving a crane used to lift the fuel assemblies on Wednesday without disengaging the handbrake.