Black Lives Matter protesters have shut down traffic in and out of Boston on Interstate 93 Thursday morning, multiple news and social media sources say.

NECN’s broadcast reports protesters tethered themselves to 1,200-pound barrels and blocked off southbound lanes in Milton and northbound lanes in Medford. Upwards of 20 protesters gathered at multiple north and southbound locations along I-93 beginning at 7:30 a.m.

Update: The state Transportation Department (MassDOT) tweets that all lanes of traffic on I-93 North from East Milton Square have been cleared of protesters and reopened.

Traffic in all lanes is moving, but commuters should expect residual delays. NECN reports motorists traveling north towards Boston from Canton can expect a commute time of roughly 50 minutes as of 10 a.m.

State police tweet that a total of 29 arrests were made in Milton and Medford. More information is expected to be released at 11:30 a.m.

Earlier: Boston emergency medical services tweets that I-93 South in Medford has been cleared of protesters and all lanes are open as of 9:11 a.m.

Northbound lanes from East Milton Square are shutdown to clear protesters; on the southbound side of I-93 in Milton, only one lane of traffic is open, state police say.

At least 23 protesters – 17 in Medford and six in Milton – have been arrested. A tweet from WBZ’s Karen Twomey suggests that total could be on the rise.

Thursday morning protests in Boston appear to be related to similar demonstrations that have reportedly broken out in Washington D.C.

Despite protests erupting at the peak of the morning rush hour, no injuries have been reported in Boston.

A press release from the group states that protests are to “disrupt business as usual” and raise awareness of police and state violence against Black people. The release continues:

Two different groups of activists linked their bodies together across the highway in coordinated actions north and south of Boston. This action was in solidarity with the Black Lives Matter movement. This diverse non-Black group of Pan-Asians, Latinos, and white people, some of whom are queer and transgender, took this action to confront white complacency in the systemic oppression of Black people in Boston.

NECN reports that southbound traffic is starting to open up but has yet to return to normal. Northbound traffic is completely shut down at this time. Ambulances have arrived on the scene and have started to divert traffic.

There are rumblings that a protest could be planned for the Tobin Bridge.

No injuries have been reported at this time.

Lt. Daniel Richard of the Massachusetts State Police tells NECN that commuters should expect residual delays as lanes slowly open up in both directions.

Here is a screengrab of a tweet from @JimmyPrinceton, which includes a press release from the protesters. NECN reports state police have made 14 arrests, but the protest is considered peaceful. Click here for the full release, posted on the Black Lives Matter Tumblr page.

On Twitter, Lt. Richard writes that protesters have been removed from I-93 but traffic is still moving slowly.

The Boston Globe reports the arrest total has climbed to 17 as of 8:45 a.m. The arrests were made in Medford.

Boston firefighters have been called to the scene to help state police free protesters who have chained themselves to 1,200-pound barrels.

NECN reports traffic metrics suggest commuters should expect delays of at least an hour as of 8:50 a.m.

Arrests totals, it appears, have jumped again. As of 9 a.m., WCVB reports, another six arrests have been made in Milton, bringing the total to 23.

The Boston branch of Black Lives Matter is asking for “jail support” for protesters arrested on I-93.

This is a breaking story; we are updating this post as more information/photos roll in.