VANCOUVER -- Two days after a cyberattack first impacted customers who rely on public transit, officials with Metro Vancouver's TransLink are providing more details on what happened.

In an emailed statement, the company's CEO said TransLink was the target of a ransomware attack.

"This attack included communications to TransLink through a printed message," Kevin Desmond said.

However, he did not provide details on what that communication entailed.

He wrote that TransLink uses "a number of tools" to monitor its IT infrastructure for such attacks, and that when it was detected Tuesday, some systems were shut down to contain the threat.

What that move meant for customers, who were only told there had been "suspicious network activity," was they could no longer use debit and credit cards to buy a transit pass. They also couldn't use their credit cards at Tap and Pay fare gates.

Vending machines were accepting cash only for customers who needed to load fares or buy a single ticket, which was an issue for those without pre-loaded Compass Card transit passes.

There were also problems with accessing stored balances for those who'd added money to their cards in person or online since Tuesday.

CTV News reached out to TransLink Tuesday, and again when the payment issues stretched into a second day, but was told no further information would be given at the time, something a cybersecurity expert called a "cop out."

The company said it was limiting its comment because the matter was under investigation, but Dominic Vogel said communication with customers is key in these types of incidents.

"Just because law enforcement is involved doesn't mean you can't be transparent," Vogel said in an interview with CTV News on Wednesday.

The attack is under investigation by Metro Vancouver Transit Police, local and national cybersecurity experts and the BC RCMP.

Desmond said the forensic investigation will look at how the incident occurred and what information may have been accessed.

"We want to assure our customers that TransLink does not store fare payment data. We use a secure third-party payment processor for all fare transactions, and we do not have access to that type of data."

Apologizing to customers impacted by the sudden shutdown, Desmond said customers can again use payment cards at vending machines and fare gates.

He added anyone who recently purchased a monthly pass or loaded cash onto their card and noticed it was missing should soon see the credit loaded.

With files from CTV News Vancouver's Allison Hurst