A group of people attacked Mukti Bhaban, the office of the Communist Party of Bangladesh (CPB), in Dhaka's Paltan area on Monday night.
The attack took place around 10pm.
The CPB blamed BNP and Jamaat-e-Islami activists for the incident, while BNP activists denied the allegation.
CPB Central Committee President Sazzad Zahir Chandan told Dhaka Tribune that a group of youths had launched a sudden attack on their office.
He blamed BNP and Jamaat activists for the attack, saying the situation stemmed from the detention and subsequent release of former Bangladesh Chhatra Union president Dipak Shil earlier in the evening.
According to Chandan, the attackers accused CPB activists of chanting “Joy Bangla”. He, however, said no such slogan had been chanted from the party office.
Officer-in-Charge of Paltan police station Ariful Islam told Dhaka Tribune that Dipak's supporters had chanted “Joy Bangla” in celebration after he was released from detention.
Angered by the slogans, some people attacked the CPB office, he said.
Police are investigating the incident and have positioned themselves between the two groups to prevent further unrest, he said.