A 40-year-old man is due to appear in court later – charged with four counts of murder and four counts of administering a poison.
Stephen John Port, from Barking, faces murder charges in relation to the deaths of four young men between June 2014 and September 2015.
He has also been charged with four counts of administering a poison with intent to endanger life or inflict grievous bodily harm, according to Scotland Yard.
Port will appear in custody at Barkingside Magistrates’ Court to face the charges.
Anthony Patrick Walgate, a 23-year-old man from Barnet, was pronounced dead after being discovered on Cooke Street in Barking on 19 June 2014.
The body of Gabriel Kovari, a 22-year-old from Lewisham, was discovered near the graveyard of St Margaret’s Church in Barking on 28 August 2014.
Daniel Whitworth, a 21-year-old from Gravesend in Kent, was also found dead near the same graveyard on 20 September 2014.
Meanwhile, the body of Jack Taylor, a 25-year-old from Dagenham, was found near the Abbey Ruins on 14 September 2015.