WRAPUP 4-Four arrested as Bangladesh building toll rises to 352
* Owner of collapsed building on run, border authorities alerted
* Angry workers protest, burning and smashing cars; dozens hurt
* Twenty-nine pulled from rubble alive, three days after disaster
By Serajul Quadir and Ruma Paul
DHAKA, April 27 (Reuters) - Two factory bosses and two engineers were detained in Bangladesh on Saturday, three days after the collapse of a building where low-cost garments were made for Western brands killed at least 352 people.
More were being pulled alive from the rubble at the building, where police said as many as 900 people were still missing in Bangladesh's worst ever industrial accident.
The owner of the eight-storey building that fell like a pack of cards around more than 3,000 mainly young women workers was still on the run.
Police said several of his relatives were detained to compel him to hand himself in, and an alert had gone out to airport and border authorities to prevent him from fleeing the country.
Officials said Rana Plaza, on the outskirts of the capital, Dhaka, had been built on spongy ground without the correct permits, and the workers were sent in on Wednesday despite warnings the previous day that it was structurally unsafe. Continued...