Toyota Motor Corp. resumed car production at all of its plants in Japan Monday for the first time since the March 11 earthquake and tsunami, but said the factories will run at half capacity due to parts shortages.

The world's No. 1 automaker said it was still struggling to secure around 150 types of auto parts. The magnitude-9.0 earthquake and ensuing tsunami destroyed parts factories in northeastern Japan, causing severe shortages of components.

The twin disasters forced Toyota to shut down all output in Japan except at three plants, which have been running at limited capacity since late March and early April to produce hot-selling Prius, Lexus and Corolla cars.

The 900 workers at Toyota's auto plant in Miyagi, one of the worst-hit areas in the disasters, observed a minute's silence for tsunami victims before starting work Monday. The quake and tsunami left nearly 28,000 people dead or missing. In Miyagi alone, police said over 8,400 people have been killed.

Toru Kuzuhara, president of Toyota subsidiary Central Motor Co. Ltd., which operates the Miyagi plant, said he hoped the resumption of auto production would help spur reconstruction efforts in the tsunami-battered region.

"We will make top-quality cars and deliver them to many customers as early as possible. I believe this will lead to broader reconstruction efforts in Miyagi," he said.

Relief at work resumption

Yasuhiro Tadokoro, an official at the Miyagi plant, said he felt relieved that the factory was again running.

"Finally, we can operate our plant. I am so relieved that we can get back to work for the first time since the tsunami," he said.

The Miyagi plant — Toyota's newest auto factory in Japan —- began operations in January. The plant suffered minor damage due to the quake, Tadokoro said. Toyota makes Yaris compact sedans at the Miyagi factory for export to North America.

Toyota will keep production at all its Japanese plants at half capacity until April 27, and then halt output from April 28 to May 9, a period that includes Golden Week holidays when factories would normally close.

The company will resume production in Japan from May 10 to June 3 at half of normal levels. Toyota has said it will make a decision in coming weeks about production plans beyond that period.

It remains unclear when Toyota will return to full production in Japan, Toyota spokeswoman Shiori Hashimoto said. Last month's disasters have caused Toyota a production loss of 260,000 cars, she said.