A man in his thirties was caught red-handed early Friday while setting fire to banners of a BNP leader on a footbridge along the Dhaka–Chattogram Highway in Siddhirganj upazila of Narayanganj district.

The detainee Riaz Hossain, 31, is son of Jakir Hossain of Bihakhair area of Kanchpur union under Sonargaon upazila.

Police said a group of miscreants set fire to several banners of the district BNP convenor Prof Mamun Mahmud on the footbridge near Madaninagar Madrasa in the Shimrail area around dawn.

Flames quickly spread across the structure, drawing the attention of nearby residents, according to police.

As locals rushed toward the bridge, the attackers tried to flee but Riaz was caught red-handed.

On information, police from Siddhirganj Station and Highway Police rushed to the scene and extinguished the fire and took the detainee under custody.

During primary interrogation, Riaz admitted that he set fire to the banners in exchange for Tk 1,000 given by an unidentified man.

He also told police that another person accompanying him poured kerosene on the banners before he lit the fire, but he claimed he did not know that man’s identity.

Prof Mamun condemned the act, saying a passerby had phoned him immediately after witnessing the flames.

“I still don’t know who carried out this sabotage,” he said. “Earlier, another billboard of mine hanging under the Kanchpur Bridge was torn down. I demand a proper investigation and the arrest of those involved.”

Officer-in-charge Mohammad Shahinur Alam of Siddhirganj Police Station said Riaz confessed to the arson during questioning.

“We are interrogating him further to identify others involved. Legal action will be taken after a full investigation,” the OC said.