CHITTAGONG/DHAKA: An 'explosives expert from a banned Islamist group' was killed in Bangladesh on Tuesday when he detonated a device while security forces searched for weapons in one of the group's hideouts, police said.

Police claimed that Mohammad Javed, 24, was an explosives expert with the Jamayetul Mujahideen Bangladesh (JMB), an outlawed group blamed for a series of deadly blasts in 2005.

The death comes amid heightened tension in the Muslim majority nation after an Italian aid worker and a Japanese farmer were shot dead last week with the self-styled Islamic State (IS) organisation claiming responsibility.

Read: Italian charity worker shot dead in BD

Police said they arrested Javed and four other JMB militants on Monday and seized a cache of weapons from a hideout in the port city Chittagong.

"Early Tuesday morning we took Javed to conduct a search for more weapons at the city's Kuaish area where he exploded a grenade. He was injured and died," Chittagong's deputy police chief Kusum Dewan told AFP.

Also read: Japanese man shot dead in Bangladesh days after ‘IS attack’

He said Javed was the "regional head of JMB's explosive unit," which has been trying to regroup after it was severely weakened in an anti-militant crackdown.

The JMB killed at least 28 people in 2005 when they carried out a series of bomb attacks on courts.

Bangladesh prides itself on being a mainly moderate Muslim country but the gruesome killings of four atheist bloggers this year have rocked the nation.

After the murder of foreigners, international schools closed temporarily and Western embassies restricted their diplomats' movements, while Australia's cricket team cancelled a planned tour due to security concerns.

Read: Murders underline rise of Bangladesh Islamist militants

Bangladesh pastor escapes knife attack at his home

A Bangladeshi pastor has survived an attempt on his life by three men who came to his home pretending to want to learn about Christianity, police and the victim said Tuesday.

On Monday, 52-year-old pastor Luke Sarker suffered minor injuries when three men aged 25-30 attacked him with a knife at his home in the northwestern district of Pabna, said the area's senior police official, Siddikur Rahman.

Sarker, the pastor of Faith Bible Church, said by telephone that the men had phoned him about two weeks ago saying they wanted to visit him to learn about Christianity.

After they arrived at his home on Monday, the men suddenly attacked him with a knife and tried to slit his throat, Sarker said. But as he shouted, his wife came to his rescue and the men fled.

Police later recovered a motorbike from outside his home. Rahman said that police had no clues yet about the identities of the three men but suspect they could be members of a fundamentalist group.

Meanwhile, police said they questioned four people Monday in connection with Saturday's attack on Japanese agricultural worker Kunio Hoshi, who was shot to death by unidentified assailants in northern Bangladesh.

The self-styled Islamic State (IS) group issued a statement claiming responsibility for that attack, according to the SITE Intelligence Group, which monitors jihadi postings online. The report could not be independently confirmed.