Two 3-ton cargo containers fell off a truck on an elevated part of the Hanshin Expressway near Kobe early Tuesday, killing a woman in a trailing vehicle and nearly smashing into Koshien Stadium, police said.

The driver of the truck, Tsuruichi Kubo, 55, of Higashimiyoshi, Tokushima Prefecture, was arrested on suspicion of breaking the safe-driving provisions of the Road Traffic Law.

The steel containers, measuring 2.5 meters wide, 5.5 meters long and 1.5 meters high, tumbled onto the west-bound lanes in Nishinomiya, Hyogo Prefecture, at around 3:30 a.m. Tuesday.

One container stayed on the road and hit a minitruck driven by 46-year-old printer Tsutomu Takenaka of Osaka, killing his wife, Tomoko, 44. He was slightly injured.

The other one smashed through the 4-meter-high expressway wall and plunged about 18 meters onto the grounds of Koshien Stadium, where it landed in front of an entrance tunnel. Amazingly, no one at the ballpark was injured, the police said.

The police quoted Kubo as saying the accident happened after he hit the sidewall, severing the steel wires that held the boxes to the truck. It is not clear why the truck hit the wall.

Kubo was transporting the boxes from Mie Prefecture to Kagawa Prefecture.