A security source from Egypt's interior ministry has denied reports that forces fired teargas at civilians during a funeral march in Port Said on Sunday.

The source said in a statement on Facebook that some people hurled Molotov cocktails and fired shots at police offices nearby the funeral which caused a fire.

Tens of thousands of Port Said residents rallied on Sunday to mourn 29 people who were killed in violence that erupted on Saturday when a court sentenced 21 defendants to death for their involvement in last year's deadly stadium riots.

Some mourners clashed with security forces when the former hurled stones and the latter fired live shots in the air and teargas to disperse them, several sources had reported.

An eyewitness told Aswat Masriya that the live shots caused no injuries but some civilians were transferred to the hospital after inhaling teargas.