New York City Mayor Michael Bloomberg's gun control group released a new ad Thursday morning featuring family members of those killed in the elementary-school massacre in Newtown, Conn.

The ad comes on the heels of a $12 million ad buy aimed at persuading Senators in key states to support key measures to reduce gun violence. This ad will air in Connecticut and is aimed at the state's gun control proposals. A source told Business Insider that a national version of the ad is being planned.

The new ad is the first to feature family members of those killed in the Newtown massacre. It features Neil Heslin, the father of Jesse Lewis; Chris and Lynn McDonnell, the parents of Grace McDonnell; Jillian Soto, the sister of teacher Vicky Soto; and Terri and Gilles Rousseau, the parents of Lauren Rousseau.

Politico's Mike Allen reported Thursday that Heslin, Rousseau, and the McDonnells will attend President Barack Obama's event on gun violence later Thursday morning in the White House. Obama is set to begin speaking at 11:40 a.m., the White House said.

The ad is part of the group's "National Day of Action," which features more than 120 events nationwide.

Here's the ad:

And here's the longer version: