TV chef Jamie Oliver's Birmingham restaurant was hit by rioters as violence spread to the city.
Jamie's Italian, a 270-seat restaurant, was targeted in the world-famous Bullring shopping centre.
He tweeted: "So sad to see what's happening in UK with these riots! All gone mad. time to get our country back. Now we need to come down hard on these idiots."
Oliver added later: "Sadly my restaurant in Birmingham got smashed up, windows all gone, whole area closed, can't open, staff and customers all safe!! thankfully."
The 36-year-old said: "My cookery school was in the thick of Clapham riot but seems they're not interested in reading or cooking as Waterstones & Resipease go left".
The Jamie's Dream School star also tweeted: "Thank u all for support!xx Thanks to the police and emergency services for what they're dealing with the communities are amazing!"
He said on the effort by Londoners to clean up after the riots: "God bless the communities getting together to sort this out. People who care about their country!!"
The star's spokesman said that his Birmingham restaurant had opened for lunch today and that one window had been smashed.
Meanwhile, TV heart-throb historian Dan Snow tweeted that he had "apprehended a rioter".
The son of Swingometer broadcaster Peter and cousin of Channel 4 news presenter Jon Snow added later: "Thanks for the messages. I was involved in one incident. The police are flat out all night. I don't know how they do it. Massive respect."
Other celebrities tweeted about the voluntary clean up effort.
Location, Location, Location presenter Kirstie Allsopp wrote: "This really gives you hope... please spread the word" while comedian Dave Gorman tweeted: "Went to bed depressed by the news. Now feeling strangely emotional as I read about riotcleanup. Amazing."
Actor Simon Pegg tweeted: "Apparently the riotcleanup site is down, likely due to an excess of traffic which is both frustrating and extremely heartening."
X Factor presenter Dermot O'Leary said: "Out and about this morning. Already seeing strangers being more considerate/friendly to each other. Makes me proud."
The show's new judge, N-Dubz singer Tulisa Contostavlos, wrote: "Absolutely disgusting what's happening, as much as everyone deserves answers from the police, destroying our city is not going to get one.
"Feel so disappointed in humans right now, didn't realise there were so many evil people on this planet, god bless the innocent ones x.
"Praying for families that have lost their homes and innocent people caught up in all this, sad times".
Singer Lily Allen, now Cooper after marrying, wrote: "Are we on the brink of civil war or something? Bring back the cane ??????".
Presenter Myleene Klass wrote: "Beyond frightening that this very second, people are having to bravely defend their homes and livelihoods from fellow Londoners."
In the US, former Spice Girl Mel B wrote: "I am really worried for everyone in the UK right now, these riots must be stopped!!".
Teen sensation Justin Bieber added: "To all the people of the UK I hope you are ok. My prayers go out to you and the amazing people there."
DJ and presenter Chris Evans wrote: "We must not lose sight of the fact that 99.999999% of the human race are ace".