Two people lost their lives on Friday when a small plane crashed on a major avenue in São Paulo, Brazil’s economic capital, before skidding into a bus, authorities confirmed.

It remains unclear whether the aircraft was attempting an emergency landing shortly after takeoff. The plane slid several hundred meters along the avenue before colliding with a bus and exploding, according to firefighter chief Ronaldo Melo.

The pilot and the sole passenger on board the King Air F90 were killed in the accident, which occurred shortly after departing from Campo de Marte Airport, a hub for domestic flights.

Fortunately, the passengers on the bus managed to escape, though six sustained injuries, Melo added.

Footage from local television showed thick smoke billowing into the sky, but firefighters quickly brought the flames under control.

Investigators from Brazil’s Aviation Accident Investigation and Prevention Center (CENIPA) are at the crash site, gathering evidence and interviewing witnesses to determine the cause of the accident.