Courteney Cox-Arquette stunned her co-stars with news of her marital split.

The actress - who issued a joint statement with husband David Arquette yesterday (11.10.10) to reveal they had began a trial separation "some time" ago - was visited on the set of her US TV drama series 'Cougar Town' by her spouse a few days ago, yet showed no indication they were no longer together.

A source said: "There was no indication anything was going on. This news today, it's very sad."

Another onlooker added to People.com: "They we're perfectly professional, though not particularly cuddly. They just talked to friends on set. None of them knew about the split until just now."

Even filming on set yesterday was normal, with a source describing it as "business as usual".

On Friday (08.10.10), David posted a picture on his twitter page from the set of the hit show, captioning it: "Courteney's 'Cougar Town dressing room'. The girl's got style."

When announcing their separation after 11 years of marriage, Courteney and David - who have six-year-old daughter Coco together - insist they "still love each other deeply".

In a joint statement they said: "We have agreed to a trial separation that dates back for some time. The reason for this separation is to better understand ourselves and the qualities we need in a partner and for our marriage. We remain best friends and responsible parents to our daughter and we still love each other deeply.

"As we go through this process we are determined to use kindness and understanding to get through this together. We are comfortable with the boundaries that we have established for each other during this separation and we hope that our friends, family, fans and the media also show us respect, dignity, understanding and love at this time as well."