A man was shot in the early hours of Monday, April 18 and taken to Royal London Hospital for treatment.
He was subsequently returned to hospital for further treatment and then released on bail until June 21.
Investigating officer, Detective Chief Inspector Stuart Smith, of the Serious Crime Directorate, said: “While this man was in hospital receiving treatment for his wounds, a substantial amount of what is believed to be heroin was recovered and this has led to his arrest.
“We want to find everyone who was involved in this truly shocking incident, which we are treating as gang related. They are putting the lives of the people of Southend at risk by carrying out their feuds on the streets of the town and we need to arrest them as soon as possible.
“I would urge anyone with information about what happened on April 18 when our victim was shot to get in touch and tell us what they know. We will take action.”
Officers were called to Southchurch Road at 12.45am on April 18 following reports that a man had been found with a shotgun wound to the stomach.
The 23-year-old was taken to hospital for treatment to his injuries, which fortunately turned out not to be life threatening. The shooting is believed to have taken place under the Malvern Flats block in Southend.
Chief Inspector Simon Anslow, district commander for Southend, said: “This attack appears to have been targeted but I am very conscious that it would be all too easy for innocent members of the public to find themselves caught up in such violence.
“Everyone in Southend has the right to go about their business without having to worry about drug dealers fighting or menacing others.
“All of my officers and staff are dedicated to protecting the people of this good town and keeping them safe. If anyone has information about drug dealers, the properties they are using, the cars and locations they are selling from or the vulnerable people they are taking advantage of, then it is vitally important that they tell us.”
Drug offences made up less than three per cent of crimes recorded in Southend last year and there were 328 recorded between April 1, 2015 and March 31 this year.
Chief Insp Anslow said: “We are carrying out covert operations to identify those responsible for supplying drugs, make arrests and execute warrants.
“But we also need the people of Southend to tell us about anything they see or hear so we can continue to build that picture and take action.”
Anyone with information can call police at Southend on 101 or ring Crimestoppers anonymously on 0800 555 111, it offers rewards of up to £1,000 for information leading to the arrest and charge of suspects.