A double-decker passenger bus transporting Ukrainian citizens has crashed in Budapest, Hungary, seriously injuring eight passengers and lightly injuring 20 more, Hungarian media have reported.

Hungarian media say the tourist bus with Ukrainian license plates was en route to Budapest Ferenc Liszt International Airport, formerly known as Budapest Ferihegy, outside Budapest when it rammed into 3.65 meters high gates, ripping off the top tier of the bus.

Police said eight people were seriously hurt and were hospitalized, with some 20 more receiving light injuries. Four passengers had to be pried out of the bus with the help of emergency workers. No children were among the injured.

Media report there were 48 people aboard the bus. Police are establishing the cause of the crash and have opened a criminal case.

Speaker for Ukraine's Foreign Ministry Mariana Betsa has commented on the tragedy.

"Unfortunately, Ukrainian tourists have been hurt. Preliminarily, 28 passengers, with eight receive serious injuries. Ukraine's consul in Hungary is assisting," she wrote on her Twitter page on Tuesday morning.