A homegrown solution to some of the world's worst traffic.
Bikers with the the Indonesia Escort Ambulance cut through the streets of metro Jakarta, horns blaring.
They wear matching uniforms And share a single goal:
To help ambulances quickly carry the critically ill to hospital and the dead to their final resting place, amid a surge in coronavirus cases in this Southeast Asian country.
Ambulance drivers say the bikers' service is invaluable.
"We feel very happy whenever these guys escort us because they can break up the traffic. We don't know how hard it would be without their help."
The volunteers make as many as 20 round trips a day through the gridlock, all at their own expense
For Sebastian Dwiyantoro it meant giving up his job as a security guard, and the safety of staying at home.
"To be honest, nowadays we feel scared of getting COVID. But I think of this as a call of duty, a call from our hearts to help."
The sound of sirens has become more common in Indonesia lately with a spike in infections linked to the Delta variant.
Meaning more work ahead for ambulance drivers - and their escorts.