SINGAPORE - Service was disrupted between Queenstown and Bugis MRT stations in both directions on the East-West line for about half an hour from 11.30am on Tuesday (July 25).

Operator SMRT announced that the closure is to allow for workers to fix a loose panel which was found to be the cause of this morning's power trips along the North-South and East-West Lines.

The glitch led to delays across the network, which were aggravated later by a track circuit fault on the East-West line.

"Engineers have traced the (power) fault to a loose panel next to the tracks in the tunnel near Tiong Bahru MRT station," SMRT said on Facebook.

"As engineers require track access to remove the panel, traction power needs to be turned off for safety."

Free regular bus services will be available from affected stations for commuters as alternative travel during this time.

"We are very sorry for the inconvenience," the operator said.

At about 11.55am, a large crowd was seen at one of the bus stops at Queenstown MRT station, with commuters looking to other forms of transportation to continue their journey.

Regular service resumed at around noon but at City Hall station some commuters were still waiting for friends affected by the disruption.

At 12.20pm, Madam Anne, 55, housewife, who declined to give her full name, had been waiting for her friend for more than hour because her friend decided to travel by bus instead given the train service disruption.

"My lunch appointment is not urgent, but I can empathise with those that have more urgent matters, especially since the disruption happened at lunch hour and many stations in the city centre were affected," she said.

Ms Giselle Chong, 24, a financial planner, waited for 45 minutes for alternative transportation to get from City Hall to Bugis.

She did not know that the train service was back up at about 12pm and was still waiting for a cab to get from City Hall to Bugis at 12.05pm.

"I was supposed to be early for my appointment at 12.30pm, but I guess I can still make it now since the disruption wasn't too long," said Ms Chong, who boarded the train at 12.10pm.

Train delays started as early as 6.30am, with several commuters claiming that they were stuck at Lakeside MRT station.

In a tweet at 7.26am, SMRT said trains are running at longer intervals due to "intermittent power fault".

"Crowds expected at station," it added.

Gene Lee tweeted: "Hey SMRT, why are you keeping quiet on the power traction fault on EWL (East-West line)? If you had tweeted it, I would have taken a cab and not be late for work."

The EWL was also hit by a track circuit fault at Commonwealth station later in the morning, with SMRT tweeting at 8.51am to warn of delays of up to 15 minutes for commuters travelling from Joo Koon to Commonwealth stations. It subsequently revised the estimate to 20 minutes at 9.33am.

Commuters who responded to the tweets however, said the delay was at least 30 minutes.

Secretary Jesse Francis, 40, told The Straits Times her normal commute from Jurong East to Queenstown took almost an hour instead of the usual 15 minutes.

"This is really out of the blue. I would normally take a taxi if I was expecting any delays," said Ms Francis.

The latest incidents come barely 12 hours after a door obstruction at Newton station caused delays on the North-south line during evening peak on Monday.

A power fault last occurred on July 12, affecting train services on both lines late at night.

Last Friday, a signalling fault caused trains to stop in between stations for over 15 minutes on the Circle Line around 10pm. Temporary clamps which came loose near Choa Chu Kang station on the North-South line also caused delays earlier that day.

SMRT has not offered explanation for these glitches, but emphasised they were not related to the new signalling system on the North-South line.

Additional reporting by Lee Min Kok