Optus is experiencing yet another mass Triple-Zero outage, which is affecting more than 14,300 customers south of Melbourne.
The telco’s website stated that an “aerial fibre break” is impacting regular and Triple-Zero calls and mobile data in the Frankston and Mornington Peninsula areas this morning.
Customers can dial Triple Zero if they are within coverage of another mobile network or call via WiFi.
Triple Zero Victoria was notified of the outage just before 8.15am and has not been informed of any issues with the community being unable to connect to the emergency line.
Optus said the outage is under investigation, and it will provide another update if there is a significant change or within six hours.
Suspected copper theft at a Telstra pit in Frankston is believed to have caused the fibre break, and the matter has been reported to police. 
Optus has been at the centre of a Senate inquiry after a failure to follow step one of an upgrade process caused a triple-zero outage that was linked to three deaths in late September.
The telco was criticised for its handling of the incident as it waited almost a day to notify the federal government.
Just days later, it experienced another Triple-Zero outage.
Optus has been at the centre of a Senate inquiry. (AP Photo/Mark Baker)
The Australian Communications and Media Authority is investigating the first outage, while Optus conducts its own internal review.
Greens Senator and Chair of the Senate inquiry into the Triple-Zero outage, Sarah Hanson-Young, has today called for an urgent review of the telco’s licence.
“Optus has failed the Australian people again,” she said in a statement.
“They are clearly not capable of providing this essential service and keeping Australians safe.”
9news.com.au has contacted Optus for further comment.