De Blasio, Homeland Security Secretary Jeh Johnson visit Chelsea

CHELSEA, Manhattan (WABC) -- New York City's mayor on Tuesday visited the Chelsea neighborhood where a bomb was set off over the weekend.

Bill de Blasio also hosted a roundtable with tenants from Visions at Selis Manor to discuss the bombing. The bomb went off next to the apartment building.

U.S. Homeland Security Secretary Jeh Johnson joined the mayor in a surprise visit to the scene and warned residents to continue to be vigilant.

"It's important to stress again, if you see something say something," said Johnson. "That's more than a slogan."

A shrapnel-packed pressure-cooker bomb exploded Saturday night in New York's Chelsea section, wounding 29 people, none seriously. An unexploded pressure-cooker bomb was found blocks away. Ahmad Khan Rahami was arrested and charged Monday.

Residents say they can't forget what happened in their neighborhood. "That guy tried to kill us, and it's hard to get your head around that," said resident Tim Peters.

The blast sent hundreds of people running for cover. Others cowered in their apartments, where artwork was knocked off the walls and windows were blown out.

"It's very easy to put your head in the ground with something like this and say I'm scared, I'm not going about my normal business, but New Yorkers are New Yorkers," said New York City Emergency Management Commissioner, Joseph Esposito.

Residents at a group home for the blind thanked de Blasio and praised the city's response. Others at a local diner told the mayor they were willing to be inconvenienced but determined not to be intimidated by the bombing.

City Council member Corey Johnson says officials have reached out to dozens of shopkeepers on 23rd Street whose stores were damaged or suffered lost business.

The New Jersey Chapter of the Council on American-Islamic Relations (CAIR-NJ) will join other Muslim organizations at a news conference in Elizabeth to condemn the bombings and to urge unity in the community.

West 23rd Street between Sixth and Seventh avenues was reopened to vehicular traffic Monday night. The south-side sidewalk of West 23 Street is reopened to pedestrian traffic, the north sidewalk remains closed due to ongoing repair work.

The Associated Press contributed to this report.