Authorities near Dallas say two armed men have been shot dead after opening fire outside of a contest for cartoon depictions of the Prophet Muhammad.
The city of Garland said two men had driven up to the art center hosting the event and opened fire on a security guard, who was injured as a result.
Police responded, shooting dead the two unidentified armed men.
The American Freedom Defense Initiative was hosting a contest that would award $10,000 for the best cartoon depicting the Prophet Muhammad.
Western art depicting the Prophet has sometimes angered Muslims and provoked threats from radicals.
In January, Islamist gunmen attacked the Paris offices of the French satirical magazine Charlie Hebdo in revenge for its cartoons of the Prophet, killing 12 people.