Police in the southern province of Binh Duong on Wednesday arrested a man for allegedly planting two home-made bombs at a Communist Party official's house last month, local news website Vietnamnet reported.
Bomb materials were found at the house of Pham Van Hung, 21, who had also threatened to kill Binh Duong Party official Do Van Cong's two children, if the official didn't give him VND175 million (US$9,188), according to police.
Cong is secretary of the Binh Duong Province Communist Party.
On April 19 a bomb exploded in Cong's garage, but no one was hurt.
Police later the same day found another bomb which included 50 grams of explosives, and a detonator connected to a mobile phone, placed in one of his cars.
Local newswire VnExpress quoted local police as saying that the mobile phone had recorded four missed calls, which may imply several attempts to trigger the bomb.
Police are continuing their investigation into the crime.