Three passenger buses were set on fire at separate locations in Dhaka on Saturday evening, while four crude bombs, locally known as cocktails, exploded in Jatrabari, leaving a rickshaw puller injured.
The incidents occurred in Mirpur, Pallabi and Badda between around 7pm and 8pm, according to police and fire service officials.
A bus of Shikhor Paribahan caught fire near Zamzam Tower in Mirpur-11 around 7:13pm.
Two Fire Service units responded to the incident. Police said passengers got off the bus safely and no casualties were reported.
Around the same time, an attempt was made to set fire to an Abhijat Paribahan bus at Mirpur-1. Police said part of a seat was burned, but the fire was extinguished by local people.
At around 7:50pm, an Alif Enterprise bus parked near the Badda U-loop was also set on fire. Local people brought the fire under control.
Meanwhile, four cocktails exploded in front of Haji Samad Market, opposite Jatrabari Police Station, around 7:30pm.
A rickshaw puller, identified as Md Billal, 32, was injured in the blasts and taken to hospital. Police said the attackers may have thrown the cocktails from a nearby flyover.
Police said CCTV footage from the areas was being examined to identify those involved. Security and surveillance have also been strengthened across the capital following a series of similar incidents in recent days.