Army experts defused the potent grenade and the mayor blamed the attack on 'a vested interest group' deeply involved in a scheme to turn Khulna into a valley of death.

Police picked up Salek, Mashiur Rahman, Salahuddin, Sajol Howlader and Zahidur Rahman, aged between 28 and 34, in different parts of the city over a case filed by Officer-in-Charge of Khulna Police Station Mosharaf Hossain as a complainant.

According to Mosharaf, Abu Salek has a history of carrying out bomb attacks in the city, dubbed as the valley of death for outlaw violence.

Explosive experts, led by Major Sajjad of Jessore Cantonment, defused the powerful grenade, thrown at the mayor's car at the main gate of Khulna City Corporation on Sunday in an assassination bid, in the police station grounds.

The mayor survived the attack unscathed, as the grenade did not explode because of the 'assailants' mistake' to take the pin off the device.

"The bomb was live and powerful. An explosion could have taken a heavy toll," the OC quoted the army explosive experts as telling.

Khulna Metropolitan Police authorities said they were trying to uncover the motive for the attempt on Tayebur's life and would pull out all the stops.

"We hope a major breakthrough in the probe soon," a top officer said.

VALLEY OF DEATH

The attack on Tayebur stirred utter security fears in Khulna, once dubbed as the city of tranquility in the confluence of the Rupsha and Bhairab rivers.

City AL president Manzurul Imam, prominent journalist Manik Chandra Saha and dozen of law-enforcers figure in the long list of casualties in the southwestern city, home to 15 lakh people.

Expressing his concern at the down-sliding law and order in the city, the peace of which is often broken by fatal bomb attacks and gunshots, Tayebur yesterday promised action to hold back the fall.

Talking to the Daily Star yesterday, he said he had very good relations with his colleagues in the BNP and leaders of all political parties.

"There is no question of the involvement of any political party or my party rivals in the grenade attack on me," he said.

Khulna district Awami League president Shaikh Harun-or-Rashid, city President Talukder Abdul Khaleque, MP, former whip Mostafa Rashidi Suja, city AL General Secretary Mizanur Rahman and top leaders of all political parties, socio-cultural organisations, Khulna Bar Association and Teachers and Employees Alliance condemned the attack.