Train services have resumed on Dublin’s northern line following major disruption on Wednesday morning.

Irish Rail has announced a number of resumptions, including a lunchtime Connolly-Drogheda train which is operating about 16 minutes behind schedule.

Various services are getting back up to speed in the aftermath of ongoing repair works.

The line between Clontarf Rd and Howth Jct was announced to have reopened after 1pm. Irish rail said services were operating with delays and may be subject to alterations as a result of the earlier disruption.

Earlier, Irish Rail said repairs to about 600 metres of overhead lines at Raheny on the nothern side of the Dart line were expected to be completed between 1pm and 2pm.

Damage to vertical lines that hold the electrical cables in place all needed repair.

Irish Rail has said there was “no indication at this time” that vandalism was behind the damage to overhead wires that disrupted services for up to 20,000 north Dublin commuters on Wednesday morning.

An out-of-service Dart was also stuck on the line with its pantographs – the connecting arms on top of dart trains – having been damaged. TIt was hauled away by another train.

In relation to possible causes Irish Rail spokesman Barry Kenny said “there may be an immediate fault with wiring, but if it gets caught up in the pantograph and the dart moves along, it can then pull down more wiring.”

Many northside Dart, northern commuter and enterprise services have been cancelled.

There was no Dart service between Malahide or Howth and Clontarf Road on Wednesday morning. Trains were operating between Clontarf and Bray/Greystones.

Northern commuter services from Drogheda and Dundalk are currently terminating at Howth Junction. There are delays and limited service between Dundalk/Drogheda and Howth Junction.

Belfast Enterprise services were reliant bus transfers between Dublin Connolly and Drogheda.

Kenny said Leap cards will be valid on all services.

Iarnród Éireann said the overhead lines at Raheny were damaged before 8.30pm on Tuesday leading to only one track being available.

The spokesman said a decision was taken to defer repair works due to a concert in Malahide attended by 20,000, to ensure customers could travel home.

Repair crews began work shortly after midnight. “Obviously, once repair work starts we need to close both lines so it is safe to effect the necessary repairs,” Kenny said.

Kenny said he was confident rail services would resume by lunchtime and that there will be services to Malahide for Wednesday evening’s Katy Perry concert.

“We apologise to everybody who is affected by this. I think if people can make alternative arrangements it would be advised to do so,” Kenny told RTÉ Radio’s Morning Ireland.

“Obviously, potentially as the morning continues, this would affect between 15,000 to 20,000 commuters and that’s obviously a hugely significant volume of people potentially deferring to other modes.

“As I say, it does arise from overhead line damage and our crews are working on site [to do] repairs but we do expect that for the entirety of the morning we will have this disruption.”