STOCKHOLM (AP) - The Swedish artist who faced numerous death threats after depicting Prophet Muhammad as a dog has been pelted with eggs by an a group of people during a university lecture on the limits of the freedom of expression. According to a police statement, Mr Lars Vilks was unharmed in the attack that occurred at Karlstad University in south-western Sweden late on Tuesday evening. No one has yet been arrested for the assault, but police say they are investigating the incident. The 65-year old artist has faced a string of threats over his 2007 sketch, which rekindled a debate over free speech and Islam that had raged a year earlier after a Danish newspaper printed 12 cartoons of Prophet Muhammad. Images of the prophet, even favourable ones, are considered blasphemous by many Muslims.