B737-800 Captain reported engine fire during taxi was extinguished and they returned to the gate.

Narrative

After normal start of engine 2 we attempted start of engine 1. (The pack and bleed air switches were configured normally. APU bleed air was used for start. Outside air temperature was only -14 degrees Celsius.). Engine 1 indications were normal during start. Fuel was introduced at 25% of N2. EGT was increasing normally. First officer noticed slightly higher fuel flow rate. Seconds after that ground crew reported engine fire. We did not have any indication of fire on the flight deck . At the same time Flight attendants called and reported fire on the left engine. We immediately run QRH procedure for an engine tailpipe fire. Fire was very short lived and was successfully extinguished. Engine EGT was not exceeded. Ground crew did not report any visible damage. They did report light dripping of fuel. We returned to the gate. The event was entered in AML. After aircraft swap we departed to ZZZ1. PA was made to the passengers trying to explain the situation. Dispatch was informed after returning to the gate. Kudos to the cabin crew. They maintained the order in the cabin and reported the fire immediately.