The police fired canisters of tear gas and gunshots to disperse the thugs, who besieged the roads, singing solidarity songs.
The gun hots caused panic as many delegates, who had yet to be accredited, scampered for safety.
One of the thugs was arrested by the police.
Some of the delegates, who spoke to our correspondent, were worried that they had yet to be accredited.
Our correspondent overheard many of them decrying the violence.
Some of them expressed displeasure over the late start, wondering if the primary would hold.
According to plans, voting was supposed to have started by 2pm but as of press time(2.11 pm), the delegates and journalists were still
outside the venue, waiting to be accredited.
Confusion as thugs threaten Lagos PDP gov primary
Peace has , however, been restored as more security had been beefed up around the area.
PDP spokesman, Gani Taofik, assured the people that everything was under control, noting that the primary would hold.