SAN DIEGO — The ordinance banning “ghost guns” signed in September by San Diego Mayor Todd Gloria is now in effect.

Untraceable guns, also known as “ghost guns,” are now banned in the City of San Diego under the Eliminate Non-serialized Untraceable Firearms Ordinance (ENUF).

“What this ordinance does is prevent the sale and possession of an unfinished lower frame or receiver, which is the trigger bang and holds the lower part of the gun unless it has a serial number on it before it is sold,” said Marni Von Wilpert, District 5, San Diego City Councilmember.

Von Wilpert told FOX 5 she knew something needed to be done after the Gaslamp Quarter shooting in April, where a gunman opened fire using a ghost gun, killing one man and injuring four others.

“I asked the San Diego Police Department if this is a big problem and they said, ‘Yes it is,’” Von Wilpert said. “They have seen a 169% increase in ghost guns in San Diego, so we took action.”

Under California law, citizens are able to make a gun at home as long as it is registered and obtains a serial number from the Department of Justice within 10 days.

Von Wilpert said the ordinance is closing the legal loophole in which criminals used to obtain gun parts to make an illegal firearm.

“Most regular guns in the city all licensed guns have to have a serial number,” Von Wilpert said. “And this just brings these ghost gun parts into that legal system to make sure that they are traceable before they are sold, before people assemble them at home.”

Gun advocates tried to stop the ordinance from going into effect with a temporary restraining order, but a federal judge denied their request.

“She wrote that this is a small, narrowly tailored law to close a loophole, the ghost gun loophole, and that it is constitutional,” Von Wilpert said.

If a person is caught defying the ordinance, Von Wilpert said they could face a misdemeanor charge that could lead to a $1,000 fine or six months in jail.