Police said Saturday they had arrested 85 suspected Islamic militants in a three-day sweep after homicide bombers killed at least nine people and wounded scores in a spate of attacks this week.

The arrests were part of a nationwide hunt for members of a banned Islamic group, Jumatul Mujahideen Bangladesh, which has been blamed for bombings across Bangladesh this year, an Interior Ministry official said on condition of anonymity because of official policy.

Police said they arrested 27 people overnight across Bangladesh while 58 suspects were detained on Thursday and Friday. The detainees have not been charged.

Authorities also stepped up security in the capital Dhaka and other areas fearing more suicide bombings by the banned group to avenge the arrests, intelligence officials said. In Gazipur, the site of two attacks this week, police wearing bulletproof jackets searched commuters near government buildings and bus terminals, police said.

Three separate attacks this week killed nine people, and three suspected suicide bombers.

A man disguised as a tea vendor set off a bomb Thursday outside a complex housing the chief government administrator's office and a courthouse in Gazipur, north of the capital, Dhaka. The blast killed one and wounded at least 29 others, authorities said.

The would-be homicide bomber was wounded and captured. He was identified as Abdur Razzak, 25, by a doctor who treated him at Gazipur Sadar Hospital.

On Tuesday, seven people were killed, including a suspected suicide bomber inside a packed library near a courthouse in the same town, area police chief Atiqul Islam said Saturday.

Also Tuesday, three bombs exploded outside a courthouse in the port city of Chittagong, 135 miles southeast of Dhaka. Two suspected suicide bombers and two police officers died.

More than 60 people were wounded in the attacks on Tuesday.

There was no immediate claim of responsibility for the blasts, but police said they discovered leaflets for Jumatul Mujahideen Bangladesh on one of the suspected bombers who was injured and captured on Thursday.

Islamic militants have repeatedly targeted lawyers and judges in Bangladesh, accusing them of promoting secular laws instead of Islamic law.

The blasts led to panic and protests in courthouses across Bangladesh this week. In some cities and towns, judges refused to attend court for fear of more attacks, private ATN Bangla television reported.

On Friday, police said they discovered and defused nine bombs that were left in plastic bags near government buildings in the city of Khulna in southwestern Bangladesh and the central town of Sirajganj.

Also Friday, a grenade was thrown at an opposition Awami League party leader in Sylhet city, 120 miles northeast of Dhaka, police said. It did not explode.

Two weeks ago, two judges were killed in the southern town of Jhalakathi by a suspected homicide attacker also allegedly linked to the banned group. Four people were killed and dozens injured in bomb attacks in August and October.

Prime Minister Khaleda Zia canceled a visit to the United Arab Emirates that was to start Saturday because of the attacks, Foreign Ministry spokesman Zahirul Haque said.