The party's senior joint secretary general suspects the placement of the object was green lit 'from the top'.
Speaking at a media briefing on Friday, Rizvi said, "How did a petrol bomb end up at BSMMU under such tight security?"
"This couldn't have happened without support or a blueprint from the top. This is what the people suspect."
On Thursday, a petrol bomb was found in front of the registrar's room on the third floor of BSMMU's administrative building.
BNP has called for tighter security at the hospital as the party's incarcerated chairperson Khaleda Zia is currently undergoing treatment in a cabin block.
"When news of the petrol bomb surfaced, many began asking us what the situation is. Everyone was shocked since the national leader Khaleda Zia is receiving treatment there."
Demanding the proper treatment and release of Khaleda, Rizvi said, "I've said before that this is all part of a big master plan. It's difficult to guage the government's intentions. Our national leader isn't well and so proper treatment for her at the hospital must be ensured."