Why was London Bridge terrorist Usman Khan out of prison and what was his sentence?

LONDON Bridge terrorist, Usman Khan was convicted of plotting to plant "Mumbai style" bombs in London in 2012 - but by 2018 he was back on the streets.

So why was the bloodthirsty extremist with links to Anjem Choudhary out of prison, and what was he sentenced to in the first place? Here's everything we know.

Why was London Bridge terrorist Usman Khan out of prison?

Usman Khan, 28, from Staffordshire, was released from prison in December 2018

He was convicted of terrorism offences, before going on to stab two people to death while wearing a hoax suicide jacket on Friday, November 29.

But the knifeman was jailed for eight years in 2012 after police uncovered a plot by his nine-strong terror cell to bomb the London Stock Exchange and build a terrorist training camp.

It's also reported the nine extremists had links to Anjem Choudhary.

In 2013, Khan's sentence was replaced with a 16-year-fixed term that saw him released after eight years without parole, after he agreed to wear a tag and have his movements monitored.

In the wake of the attack the Ministry of Justice promised that "the licence conditions of every terrorist offender" would be reviewed going forward to ensure conditions "are as tough as they need to be".

A spokesman said on Saturday they were also "stepping up our already frequent meetings with these offenders".

What was Usman Khan's sentence?

Khan was originally ordered to serve an undetermined number of years under an Imprisonment for Public Protection (IPP).

The IPP is crafted for those who authorities view as a risk to the public.

Under the IPP he would have no minimum sentence and only be released after consideration from a parole board.

At the time of Khan's original sentencing, authorities struggled to determine whether Khan and the rest of the terrorist cell who planned the London Stock Exchange attacks could have carried out the deadly plan - or whether they were "fantasists."

Regardless, Khan's vile extremist views deemed him a threat to society, and a judge ruled that he should be locked up.