A gang member breached an injunction by filming a music video with violent lyrics.
Sahin Korta-Haupt is a member of the so-called C17 gang in Thurrock, who were made subject of a gang injunction in September 2018.
The court order bans them from large parts of Thurrock and restricts certain behaviour.
But the 19-year-old, formerly of Junction Road, Gillingham, breached four of the conditions.
He appeared in a drill music video with violent lyrics, which was posted on YouTube on June 30 this year.
This breached the injunction, which prevents him from featuring in any audio or video online that is threatening, abusive, insulting, incites violence, promotes criminal activity, shows weapons or makes reference to gang affiliations and the C17.
He also breached a condition banning him from congregating in a public place in a group of two or more where the group was behaving in a way likely to make a person feel intimidated or afraid for their safety.
Korta-Haupt also wore a hooded top and associated with another gang member in a public place.
He was arrested on Friday October 11 and sentenced at Chelmsford County Court on Monday.
He received 129 days in a young offenders institution and was also ordered to pay £300 costs.
PC Jonathan Kemp, of the Operation Raptor team, said: “We will continue to enforce the injunction, which we worked with the support of our partners to secure.
“We will do everything we can to prevent the further exploitation of young people who have been lured into the gang lifestyle with misleading promises of a glamorous lifestyle.
“Violent drill videos only serve to fuel those misleading impressions of gang life.
“The reality is that young people – especially those who are vulnerable - will be at risk of violence, crime and exploitation.”
Anyone with information about drug dealing or gang activity in their area should call 101 (or 999 in an emergency), or Crimestoppers anonymously on 0800 555 111 or use the anonymous online form at Crimestoppers-uk.org
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