Eight people have been charged following the drug raids across Greater Manchester.
They will all appear at Bolton magistrates' court today charged with conspiracy to supply drugs.
On Wednesday, officers raided eleven addresses as part of an operation to disrupt the activities of a suspected organised crime group.
Warrants were executed across the Bolton, Bury, north Manchester and Salford areas of Greater Manchester and a number of properties.
Officers were investigating the sale of approximately 313 kilograms of mephedrone with the street value of £3.8 million through an online website, which was run from a unit in Bolton.
More top news
Showers or longer spells of rain. Severe gales on Sunday with storm force winds for coasts and hills
Tyson Fury plans to give his fans a song when he's finished with world heavyweight champion Wladimir Klitschko on Saturday night.
Often very windy, especially as we head into Sunday, with rain or showers. Met Office 'Be Aware' warnings have been issued