London police say that they have arrested 182 activists who tried to breach the Olympic Park's security cordon during the Olympics opening ceremony.
Scotland Yard said that four people have been charged with various offenses, while the rest were bailed pending further questioning.
Police said earlier that they were aware that a monthly protest by cyclists was planned for Friday but ordered the protesters to remain south of the River Thames.
That was to keep them from blocking more than 80,000 ticket-holding guests from attending the Olympics opening ceremony.
Police said scores of cyclists defied warnings and crossed the river to the Stratford area, where the Olympic Park is located. They said officers began arresting the cyclists after they ignored verbal warnings to leave the area.