Two prison inmates have been charged with the attempted murder of drug kingpin Tony Mokbel, who remains in a critical condition in hospital.

Police on Tuesday confirmed the pair, both aged 21, had been charged with attempted murder, intentionally causing serious injury and causing serious injury intentionally in circumstances of gross violence, stemming from a stabbing at Barwon Prison yesterday.

CCTV showed Mokbel, 53, being attacked by two men of Pacific Islander appearance in an exercise yard of the prison complex.

Mokbel remains in a critical condition recovering from surgery, while Barwon Prison is still in lockdown.

“The information I have is he’s in a critical but stable condition. Nothing that I’ve been told is leading me to believe it’s life-threatening,” Dr Cassar told 3AW radio.

Dr Cassar said good quality security camera footage of the incident has been handed to police showing Mokbel walking back towards a unit in the mainstream compound of the jail when attacked.

“He was approached by two prisoners who assaulted him, knocked him to the ground and you can see the footage very clearly, showing a number of stabbing actions,“ she said.

“Another prisoner did come to Tony Mokbel’s aid it seems, and he was also injured.

“In terms of the relationship between those two people, it’s too early to tell.”

The other injured man is in Geelong Hospital in a stable condition.

Dr Cassar said authorities separated the attackers within moments and placed them in a high-security unit.

They will be interviewed by police and prison authorities, who will also investigate who else is involved.

Three homemade weapons were recovered nearby and have been handed to police.

“These sort of incidents are unacceptable and for me, it’s a real worry this has occurred,” Dr Cassar said.

“We’re doing everything we can. We’ll certainly wait for the Victorian police investigation and then my team will investigate, and there’ll be an external review into this.”

Dr Cassar said it is too early to tell if the incident related to a “powerplay“ within the jail.

The stabbing came a day after News Corp Australia reported Mokbel had become an enforcer and was in dispute with a group of Islanders.

Mokbel hit the headlines in recent weeks after news broke that his former lawyer had acted as a police informer, dishing dirt to detectives to help secure convictions.

Dr Cassar said the lawyer informant scandal, which opened a possible window for Mokbel to appeal, would also be considered.

“He was very confident he would get out of jail,” Dr Cassar said, adding she suspected it “probably was” irritating other prisoners.

Dr Cassar said Mokbel’s security requirements didn’t require he be placed in high security and he had been housed safely in the mainstream jail population for many years, without issue.

After fleeing Australia while on trial in 2006, Mokbel was captured in Greece in 2007 and was sentenced to a 30-year jail term for drug crimes, with a minimum of at least 22 years before being eligible for parole.

Mokbel was stabbed in the same prison where fellow gangland identity Carl Williams was murdered in April 2010 by another inmate, Matthew Charles Johnson.