WRAPUP 3-Four arrested as Bangladesh building toll rises to 341
* Owner of collapsed building on run, border authorities alerted
* Angry workers protest, burning and smashing cars; dozens hurt
* Twenty-one pulled from rubble alive, 72 hours after disaster
* Rescuers in frantic bid to save 15 trapped factory workers
By Serajul Quadir and Ruma Paul
DHAKA, April 27 (Reuters) - Two factory bosses and two engineers were arrested in Bangladesh on Saturday, three days after the collapse of a building where low-cost garments were made for Western brands, as the death toll rose to 341 but many were still being found alive.
As many as 900 people could still be missing, police said.
The owner of the eight-storey building that fell like a pack of cards around more than 3,000 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. Continued...