Simon Cowell has publicly praised Olly Murs after he hit the top of the charts.

Murs, who came runner-up on the 2009 edition of the X Factor and currently hosts spin-off show Xtra Factor, hit No.1 in the UK singles chart on Sunday (November 25) with his track 'Troublemaker'.

X Factor supremo Cowell took to Twitter today (November 26) to heap praise on the cheeky singer, complimenting his personality. He said:

"Hi Olly Murs. Congratulations on your number one single today. You are a true star and a great guy. Proof success doesn't change you."

Cowell meanwhile later took a stab at Depeche Mode's Martin Gore for seemingly promoting gun violence, tweeting: "I read Martin gore wants to shoot me. He was is in depeche mode. Do you realise how weird and stupid that makes you. Go and watch the news."

The X Factor USA judge continued: "Why I am angry about weirdo gore is a ton of people have got shot this year and people like weirdo gore encourage this."