Trains will be available at a frequency of 20 minutes till 6 am and then will continue as per timetable

Metro services will begin early on Sunday on account of a half-marathon event in the national capital in the morning, officials said.

The 15th edition of the Airtel Delhi Half-Marathon will see one of the best line-ups of international elite athletes with seven sub-60 minute runners in the men's category and nine sub-70 minute runners in the women''s category.

"In light of the 2019 Airtel Delhi Half-Marathon on October 20, services will begin at 4 am from all terminal stations (except the Airport Express line).

"Trains will be available at a frequency of 20 minutes till 6 am and then, the services will continue as per the Sunday timetable," a senior Delhi Metro Rail Corporation (DMRC) official said.

The current Delhi metro network span stands at 377 km with 274 stations, including the Noida-Greater Noida aqua line.