HALIFAX -- Much of Atlantic Canada lost cellphone and other network services for more than four hours Friday, inconveniencing citizens and commerce alike, after what Bell called "accidental damage" to its fibre optic grid.

Bell said its "major service outage" hit internet, TV, wireless and landline phones, with landline 911 service intermittent.

In St. John's, N.L., Lauren Halliday said the outage came at a particularly bad time for her family as her sister was at home and expected to go into labour at any time.

"My sister is supposed to have a baby today or tomorrow so we were kind of sweating about that, making sure that she had a car to get to the hospital and stuff," she said in an interview on Friday.

"I tried to make a few phone calls and nothing would go through."

Flights were delayed at multiple airports, many consumers couldn't use their debit and credit cards, and TD Canada Trust was among the banks closing some branches in the region.

Bell said the outage began at 10:45 a.m. AT, with service restored at 3 p.m "following rerouting and repair of network infrastructure."

"This was an extraordinary situation in which major fibre network links serving Atlantic Canada were cut by third-party construction work in two different locations," said spokesman Nathan Gibson in an email.

"We are still investigating how the fibre cuts happened."

Telus spokesman Richard Gilhooley said his company's services, which rely on Bell infrastructure, had also been restored.

The outage dominated social media in the region, with Twitter user Cody Neal joking: "I have no way of communicating with my wife about what we're having (for) supper other than walking upstairs and asking."

An Ontario Twitter user, Jordan MacKinnon, joked: "My thoughts and prayers are with those in Atlantic Canada, who are currently being forced to speak to each other like it's 1994."

A spokeswoman with Rogers and Fido said their cellular network was not affected. Eastlink said in a statement "an interruption impacting our network partners ... may affect your ability to place calls."

Telus subsidiary Koodo was also knocked out by the outage.

The situation prompted emergency services in St. John's, N.L., Saint John, N.B., and other Atlantic cities to deploy emergency vehicles at strategic locations for people who couldn't call ambulances using normal methods.

Halifax Stanfield airport said some flights were affected, and Air Canada said computer issues hit flights at multiple Canadian airports. WestJet said its Moncton call centre is "offline," and asked customers to call later unless the matter was urgent.

The outage appeared to hamper emergency communications in some parts of the region, and people were advised to try non-emergency numbers if 911 didn't work.

Officials in Halifax said emergency services were available throughout the outage, although some first responders had issues with their phone service.

They said in a statement that the Halifax fire service told all volunteer firefighters to head to unstaffed fire stations "as soon as possible, to ensure smooth communication between our dispatch operators and individual stations as well as being on-hand to assist citizens who need emergency assistance."

It wasn't the first time a damaged cable suddenly sliced normal telecommunications service in the region.

In the fall of 2011, Bell Aliant said a cut fibre optic line in northern New Brunswick caused a three-hour outage.

On that occasion, line damage forced a switch to a backup system, which didn't work consistently.

With files from Sue Bailey in St. John's, N.L.