Bangkok police arrested a foreign man on 29^th afternoon, the man is main suspect in Bangkok explosion. In the arresting locale, lots of material for making bomb were seized. Local time about 1:00pm, abuout 100 Tai policemen surrounded a residence on the east of Bangkok. Policemen finally took action after 2 hours arrangement, and arrested a turkish man on the forth floor. Lots of material for making bomb and some 0.5cm in diameter ballpoints were seized, which were similar with the things found on explosion locale.