"Today's OHE issue involved the breaking of a copper split pin inserted in the insulator meant to support return current wire. This resulted into short circuit of earth wire with 25 KV live conductor," Delhi Metro Rail Corp (DMRC) spokesperson Anuj Dayal said in a statement.
He said the corporation had begun now to replace such copper pins with stainless steel pins for better longevity. The entire exercise will take five months to be completed.
The Yellow Line connects north Delhi and Gurugram in Haryana and covers four inter-change stations including Hauz Khas, Central Secretariat, Rajiv Chowk and Kashmere Gate.
When they were stuck, people in the coaches frantically advised others not to take the Metro through Twitter and complained they were feeling claustrophobic inside the packed coaches.
"It's heavy crowd here, people are suffering... trapped in Metro. Please take immediate action," tweeted one commuter.
Another begged Metro to act, saying the coaches were struck for 30 minutes.
The Metro said: "The problem could be identified through careful physical identification of each and every OHE mast of the affected 6.6 km long section from Sultanpur to Guru Dronacharya station.
"That is why it required OHE patrolling teams around two hours to identify the exact affected OHE mast. Once it was identified,the repair was done within 15 minutes."
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)