Metal and concrete security barriers were installed on Blackfriars Bridge in the early hours of Thursday morning, after similar defences were installed on other Thames crossings earlier in the week.
Heavy-duty defences have now been placed on Lambeth Bridge, Westminster Bridge, Waterloo Bridge, Blackfriars Bridge and London Bridge.
On Blackfriars Bridge the new barriers have had an effect on cycle superhighway 6, with narrow gaps for bicycles to pass through.
The northbound bus stop on the southern end of the bridge has also been closed until further notice.
The new barriers on cycle superhighway 6 at Blackfriars Bridge. pic.twitter.com/UwjHDYaV9B
— London SE1 (@se1) June 8, 2017
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