ONDON — Vehicle barriers along the roads around the All England Club were the most noticeable changes as Wimbledon began Monday under beefed-up security after a series of attacks around London in recent months.
Richard Lewis, the club’s chief executive, said most of the new measures were “below the radar.” Among the changes visible to spectators and players at the tournament were the installation of the waist-high black barricades around the outside of the grounds and the presence of armed officers at each gate.“(The blockers) have been put in based on recommendations of the security services for obvious reasons because of recent terrorist attacks,” Lewis said.

Security has become a greater concern in England in recent months. A man drove into pedestrians on Westminster Bridge in March, killing four and fatally stabbing a police officer outside Westminster Palace. Last month, attackers used a vehicle and knives to kill eight people and wound dozens on London Bridge and in nearby Borough Market, and in a separate incident, a man drove into people spilling out mosques in the Finsbury Park neighbourhood after Ramadan services.