* Police chiefs from Newtown, Aurora meet at White House
* Obama says he needs cooperation of Congress (updates with quotes from Obama)
By Jeff Mason and Roberta Rampton
WASHINGTON, Jan 28 (Reuters) - President Barack Obama turned to law enforcement on Monday for support in his push to tighten gun laws, meeting at the White House with police chiefs from cities scarred by mass shootings and calling for more officers nationwide.
Obama, who has made stricter gun control measures a top policy goal for this year, reiterated his desire that lawmakers pass measures he recently unveiled to curb gun violence, including an assault weapons ban and universal background checks for gun purchases.
The meeting was the latest in a series of discussions that Obama is using to try to build political support for tighter gun control after 20 young children and six adults were killed in December by a gunman at a school in Newtown, Connecticut.
Newtown's police chief, Michael Kehoe, attended the meeting along with his counterparts from Aurora, Colorado, where 12 people were killed and 58 wounded in a mass shooting at a movie theater last July, and from Oak Creek, Wisconsin, where six people were killed and four wounded at a Sikh temple in August.
In remarks to reporters at the start of the meeting, Obama noted that the police chiefs realized the problem of gun violence extends beyond high-profile mass shootings.
"That's why part of the conversation that we're going to be having today relates not only to the issue of new laws or better enforcement of our gun laws, it also means what are we doing to make sure that we've got the strongest possible law enforcement teams on the ground?" Obama said.
"What are we doing to hire more cops? What are we doing to make sure that they're getting the training that they need?" he said.
Obama wants to ban military-style assault weapons and ensure that all gun buyers are subjected to background checks. But he needs Congress to pass legislation on the politically tricky issues.
The Senate Judiciary Committee will hold its first hearing on Wednesday on the measures.
"The only way that we're going to be able to do everything that needs to be done is with the cooperation of Congress," Obama said.
"That means passing serious laws that restrict the access and availability of assault weapons and magazine clips that aren't necessary for hunters and sportsmen and those responsible gun owners who are out there. It means that we are serious about universal background checks," he said.
The National Rifle Association, the country's most powerful pro-gun lobby group, has vowed to defeat the plan, which it says would infringe on gun ownership rights protected by the U.S. Constitution.
Monday's meeting included Vice President Joe Biden, U.S. Attorney General Eric Holder and Homeland Security Secretary Janet Napolitano.
Obama and Biden have said their plan would not affect the rights of responsible gun owners. Biden traveled to Richmond, Virginia last week with that message. (Editing by Xavier Briand)