Rapid Action Battalion (RAB) said they initially arrested the protestor but his accomplices attacked the elite anti-crime unit of police, sparking a shootout in northwestern Chapai Nawabganj district.
The deceased was an arsonist who torched vehicles and threw crude bombs in the region to enforce the opposition BNP's nation-wide blockade, said a statement issued by RAB hours after the incident.
BNP's Chapai Nawabganj unit in a statement said the 35-year old protestor, Motiur Rahman, was an activist of their youth front.
The security forces' action came a day after paramilitary Border Guard Bangladesh (BGB) chief Major General Aziz Ahmed warned of using guns against arsonists to protect lives of people as well as members of law enforcement agencies.
"If someone is seen setting fire on a vehicle we will use ours guns as one casualty will save lives of five (several) others...and if they attack us with petrol bombs we will not chase them with batons, rather shoot them for self defence," Ahmed said in a press conference late yesterday.
Despite the warning, suspected opposition activists overnight set ablaze four trucks, injuring two drivers in northwestern Sirajganj and northeastern Feni.
In one of the incidents in northwestern Pabna, unidentified activists last night stopped a potato-laden truck on a highway and torched it using petrol bombs.
Activists have taken to the streets across the country for the last 11 days to try to enforce a transport blockade called by main opposition leader Khaleda Zia, demanding resignation of Prime Minister Sheikh Hasina.
The opposition yesterday also called a 12-hour strike to protest an assassination attempt on one of Zia's longtime aides, Riaz Rahman, on Tuesday.
Rahman, a former junior minister for foreign affairs and adviser to Zia, survived after being shot four times in his car which was also set alight in an attack the opposition blamed on the government.
The violence has claimed 25 lives since Zia called indefinite transport blockade over the first anniversary of January 5 controversial polls which was boycotted by opposition parties.
Former Prime Minister Zia, who has been "confined" in her Gulshan office, called non-stop blockade on January 5 when police barred her from joining her party's rally.
The government and the ruling Awami League leaders rejected the allegation of Zia's confinement calling it a "self-staged political drama" and said that Zia could go home or anywhere anytime with police escorts.
They said existing police siege around her office was meant for her own security and she could stage peaceful rallies and meetings if she wanted.
Prime Minister Hasina has urged her arch-rival to shun the "path of violence" and reorganise her party for the next elections scheduled for 2019.
Meanwhile, the United States, Britain and the European Union, sharply criticised the current spate of violence in the country, calling on all parties to exercise restraint and also condemned the assassination attempt on Zia's aide Rahman.
"We call on all parties to exercise restraint and eschew violence and intimidation, and we urge the government to ensure people can freely exercise their right to peaceful political expression," the US State Department said in a press statement two days ago.
Deputy spokesperson of the state department Marie Harf added: "There is no justification for such outrageous and cowardly acts in a democratic Bangladesh. We condemn the use of violence for political objectives."
The heads of mission of the European Union resident in Bangladesh called on foreign minister A H Mahmood Ali and expressed concern over the "shrinking of democratic space".
British High Commissioner to Bangladesh, Robert Gibson, in a press statement expressed concern over the attack on Rahman, and continuing reports of violence from across Bangladesh.
The US State Department in its statement said the US was shocked and saddened by the attack on former foreign secretary Rahman and asked the Bangladesh government to investigate and hold accountable those responsible for the attack.

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