Source: Andrew Johnson | www.nbcsandiego.com

A San Diego flight headed to Denver was delayed for hours Tuesday after smoke could be seen coming from the plane parked at the San Diego International Airport.

A battery-type charger overheated inside a piece of luggage in the cargo bin of a Southwest Airlines Boeing 737 at around 11:30 a.m., according to Dan Landson with Southwest Airlines.

“The airline reported smoke coming from the belly of an aircraft while it was parked at one of the gates,” said Rebecca Bloomfield with the San Diego International Airport.

Ramp agents loading luggage onto the plane noticed the issue and removed the overheating bag, Landson told NBC 7. The agents then notified local fire crews for assistance.

The San Diego Harbor Police Department and San Diego Fire-Rescue responded to the airfield, according Mónica Muñoz with SDFD.

By the time SDFD crews arrived at 11:45 a.m., Harbor PD had already put out the smoke, Muñoz said.

Firefighters “assisted with cooling off the electronic device,” Landson told NBC 7.

The Boeing 737 was taken out of service and passengers were loaded onto a different aircraft, Southwest Airlines said.

The trip, originally scheduled with an 11:25 a.m. takeoff, was delayed until 2:40 p.m. Passengers arrived in Denver at 5:45p.m., approximately three hours late.

“The Safety of our Employees and Customers is of utmost importance and we thank our Customers’ patience during this situation,” Landson said in a statement released to NBC 7.