- The Red Cross says the best way to help right now is to get in touch with loved ones through its Safe And Well Listings. The organization is not asking for blood donations at this time.
- The Salvation Army is offering food, beverages and crisis counseling to survivors and first responders. Find out how you can get involved here.
- Some marathon runners are stranded in Boston and in need of places to stay. Find out how you can offer housing here.
- Anyone with info about the incident can call 1-800-494-TIPS.
Additional sources to find loved ones and get help locally at ABC News.