Two buses collide in Barcelona, 34 injured

The four critically injured were taken to hospital, including one who was temporarily "trapped" in one of the buses, emergency services in the northeastern region of Catalonia wrote on social network X.

Officials have not yet released the nationalities of the injured.

The accident happened on Avinguda Diagonal, one of Barcelona's widest and most significant avenues, not far from the centre of the city.

It comes as Barcelona and much of Spain were lashed by rain and it snarled traffic in Barcelona on the opening day of the annual Mobile World Congress (MWC), the world's largest wireless technology showcase which is set to draw around 100,000 attendees.

According to witnesses quoted by Barcelona-based newspaper La Vanguardia, one of the buses hit the other from behind, which in turn crashed into a tree.

Images posted on social media showed a green and white bus embedded against a white one, with several ambulances deployed nearby.