According to details, the detained leaders include Farooq Sattar, Khawaja Izharul Hassan, Arshad Vohra, Khawaja Sohail and Dr Aamir Liaquat Hussain.
Party’s official website has also been shut down.
Video clip from the moment outside Karachi Press Club shows the MQM senior leader Sattar asking the official for two minutes, but the Rangers official insists and takes him away.
Farooq Sattar went to press club for a press conference after MQM party’s workers turned to violence after being told by their party chief to surround the offices of Geo News, Samaa and ARY.
Sindh Rangers’ spokesman confirmed that MQM leaders Farooq Sattar and Khawaja Izharul Hassan have been taken into custody.
He said that both leaders had come to Karachi Press Club for media talk.
Earlier during the day, at least one person reportedly injured in the firing near Zainab market succumbed to his wounds at the hospital after the violence.
Two other people sustained injuries during the violent attacks in which around 2000 party workers participated.
The workers also caused damage to shops located in Zainab market in the Saddar area of the city forcing owners to close.
Traffic jams were witnessed in areas surrounding I.I.Chundrigar road, while the road leading to CM House was also shut.
Windows of several vehicles broke due to stone-pelting by MQM workers. More than one dozen people were arrested by the authorities.