The gunman who opened fire at a crowded gay nightclub in Orlando early Sunday morning left about 50 people dead and dozens more injured, flooding hospitals with those who were hurt. As federal and local authorities continued to investigate the attack at the Pulse Orlando club, people across the city and the country mourned the victims and began searching for ways to respond.

Here’s how you can help the victims:

Donate Blood

The OneBlood center put out an urgent call for blood donations for the Orlando victims on Sunday, and received an overwhelming show of support. Donors were told that blood bank had reached capacity but encouraged to return in the coming days, according to the Orlando Sentinel.

“I’ve been here 13 years and never seen a response like this,” Pat Michaels, a spokesman for OneBlood, told the Sentinel. “The sentiment is understood and appreciated, but it’s a little too much, too soon.”

These are the federal rules on who can donate blood.

Donate Money

Equality Florida set up a donation page on GoFundMe to support the victims. The fund has raised more than $120,000 from more than 3,000 donors since being set up.

Attend a Vigil

Vigils were planned in major cities across the country. Details are still being determined as of early Sunday afternoon. Orlando’s LGBT community postponed plans for a vigil following guidance from law enforcement, the Sentinel reports.

Provide Counseling

The Gay, Lesbian, Bisexual, Transgender Community Center of Central Florida asked counselors from the Orlando area to come in and help field phone calls on a hotline, the Sentinel reports. Those who would like to speak to a counselor can call 1-407-228-1446.

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