Friday morning’s fire destroyed important documents, Bashikpur Union land office’s Md Azad said.
Police put out the flames within 30 minutes and rescued the village defence force personnel.
Land record offices have been frequently targeted during the BNP-led alliance’s ongoing anti-government agitation across Bangladesh.
Azad said the security officials -- Anowar Hossain, Abdus Sattar and Belal Hossain -- were unharmed.
Quoting them, land office staff Mostofa Kamal said a group of about 12 armed masked men held the trio hostage at gunpoint.
“The attackers fled after setting fire to the office,” he said.
The extent of the damage was yet to be ascertained.