Police arrested the balloon vendor in connection with a case filed over Wednesday’s cylinder blast at Rupnagar Residential Area in Mirpur, which left seven children dead and 20 others injured, from National Institute of Traumatology & Orthopaedic Rehabilitation in the capital on Thursday morning.

Earlier, Sub-Inspector of Rupnagar Police Station Sumon filed the case against Abu Syed in this connection around 3:00am.

However, another victim, injured in the cylinder blast, died at Dhaka Medical College Hospital early Thursday, raising the death toll to seven.

The deceased was identified as Neha, 8.

Abul Kalam Azad, officer-in-charge of Rupnagar Police Station, said Neha succumbed to her injuries around 5am.

Six children were killed and 21 people injured in the cylinder blast while gas was being pumped into balloons by a vendor in Rupnagar Residential Area of the city on Wednesday afternoon.

All of the deceased were residents of Quamrul Matbarer Bosti (slum).