US President Joe Biden is to target homemade "ghost guns" as part of a new set of measures to tackle gun violence, a White House official has said.

Ghost guns have no serial numbers, making them difficult to trace. They can be bought by minors and people who would not pass background checks.

Mr Biden will enact the measures through an executive order, meaning he will not need approval from Congress.

The move comes after high-profile mass shootings last month.

A total of 18 people died in two mass shootings, one in Boulder, Colorado and the other in Atlanta Georgia.

The executive order will include measures on the use of stabilising braces and community violence prevention.

However, the president will have an uphill task. The right to bear arms is protected by the Second Amendment to the US Constitution and many people see gun control laws as infringing on their constitutional right.
What are the proposed measures?

Later on Thursday, Mr Biden will say that he has given the Justice Department 30 days to propose a rule that will help reduce the number of "ghost guns". These guns are self-assembled, which means they do not contain a serial number and cannot be traced.

Mr Biden will also give the Justice Department 60 days to come up with a rule on stabilising braces for pistols. Under the rule, the braces, which can be used to turn a pistol into a short-barrelled rifle, would be subject to regulation under the National Firearms Act.

The Justice Department will also be asked to draft a "red flag law" which states can then use to create their own legislation. These laws authorise the courts and law enforcement to remove guns from people thought to be a risk to the community.

An official told Reuters news agency that this was just the first step in tackling gun violence and that Mr Biden would continue to advocate for gun legislation.

"The president will not wait for Congress to act before the administration takes our own steps, fully within the administration's authority and the Second Amendment, to save lives," the official said.

Getting further steps through Congress would be difficult. The US Senate is currently split 50-50 between Democrats and Republicans, with Democratic Vice-President Kamala Harris holding the deciding vote.

However, because of Senate rules, in practice 60 votes are needed to pass legislation, so some Republican support is required. Republicans have blocked significant gun control laws in the past.
What has the reaction been?

Mr Biden's proposed measures have been praised by gun control group Everytown for Gun Safety.

"Each of these executive actions will start to address the epidemic of gun violence that has raged throughout the pandemic and begin to make good on President Biden's promise to be the strongest gun safety president in history," group president John Feinblatt said.

He added that the Biden administration's decision to treat ghost guns "like the deadly weapons they are will undoubtedly save countless lives".

The National Rifle Association, the biggest gun rights lobby group in the US, described the measures as "extreme" and said it was ready to fight.

The Colorado supermarket shooting was the seventh mass killing in the US so far this year, according to a database compiled by the Associated Press (AP), USA Today and Northeastern University. The database defines mass killings as four or more dead.