Consecutive days of mass shootings have left two cities more than 1,500 miles apart in mourning.

It started Saturday, when a man walked into a Walmart in El Paso, Texas, and started shooting. Authorities said Patrick Crusius, 21, started shooting inside the grocery story shortly after noon, and then continued toward the nearby Cielo Vista Mall.

>> RELATED: What we know about alleged El Paso shooter

Less than 24 hours later, suspected gunman Connor Betts, 24, opened fire with a .223-caliber rifle in Dayton, Ohio, before being shot down by police.

>> MORE: Soldier from Georgia tried to save kids during El Paso mass shooting

Twenty-nine people were killed and dozens more were injured between the two attacks, leaving the country reeling.

President Donald Trump has ordered flags at federal government buildings be flown at half-staff in honor of the shooting victims. The flags will remain at half-staff until sunset on Aug. 8.

>> RELATED: Dayton shooting suspect ID'd, reportedly had prior hit-list

Here’s how you can help victims impacted by the tragedies:

  • Donate to victims

Several funds have already been created to assist victims of both the El Paso and Dayton shootings to cover the cost of medical expenses and other necessities.

Dayton Mayor Nan Whaley announced that The Dayton Foundation has set up a tax-deductible fund that is accepting donations for the victims and their famililies and friends. The Dayton Oregon District Tragedy Fund will help those impacted by the shooting, officials said.

Those interested in contributing can donate at The Dayton Foundation website.

A fund through the Paso del Norte Community Foundation is collecting money to support victims of the El Paso shooting and their family members. Anyone interested in donating to the El Paso Victims Relief Fund can donate by visiting the community foundation's website.

  • Donate to a charity

Some charities, like the American Red Cross, exist specifically to aid victims of tragedies. The Red Cross, which bills itself as an organization that “alleviates human suffering in the face of emergencies” said in a statement Sunday that it is collaborating with emergency officials to help those impacted by the shootings.

"Our hearts go out to all those affected by the tragedies in El Paso, Texas and Dayton, Ohio," the organization said in a statement. "The American Red Cross is working in close coordination with emergency officials to provide comfort and support to the affected communities.

  • Give blood

In a statement Sunday, the Red Cross said that it had all the blood it needed to support victims in both Dayton and El Paso. However, the organization said the incidents show that it is the blood that is already on the shelves that helps during emergencies.

“Unfortunately, fewer blood donors and blood drives during the summer months make it one of the most challenging times of the year for blood and platelet donations,” the statement said.

Donors can give blood anytime by making an appointment at bloodhero.com.