It looked like armed police or an armed gang were storming the old Toys R Us stores in Cardiff Bay on Friday morning.
Shots were heard and the raid was caught on camera by a local resident. But there is no need to worry.
It was not a hostage situation, but part of the latest filming for the new TV version of War of the Worlds .
The former Toys R Us store, which has been empty since closing down in April last year , was transformed into a French supermarket for the filming.
The series is set to debut later this year, broadcasting on FOX in more than 50 countries across Europe & Africa and on CANAL+ in France.
Filming has been taken place across south Wales for several months.
Earlier this month, the crew took over the Senedd chamber with actors wearing army fatigues seen sat in the chairs usually frequented by Assembly Members in the siambr.
Gabriel Byrne and Downton Abbey star Elizabeth McGovern will lead the cast and Cold Feet's Daisy Edgar Jones, Natasha Little from Silent Witness, and Guillaume Gouix also star.
It has been created and written by British TV writer of Hotel Babylon, New Tricks, Hustle, Harley Street and Merlin, Howard Overman.
Cardiff council confirmed that filming had been organised through its film office.
