Police will begin enforcing harsher new traffic laws on Saturday, which includes arrest and detention for joyriders, running red lights and driving under the influence of alcohol, a top police official said.

If a motorist kills someone by running a red light, it would be considered a criminal offense under the new rules, said Col. Fahd Al-Abdan, spokesman of the Qassim police department.

Interior Minister Prince Mohammad bin Naif had ordered the traffic officers to enforce the legislation, he said.

Joyriders causing accidents would be detained, he said.

Police officers would also arrest those driving under the influence of alcohol, and in the wrong direction, he said.