NEW YORK (CBSNewYork/AP) — As donations continue to pour in for two NYPD officers gunned down last weekend, the Stephen Siller Tunnel to Towers Foundation announced Sunday it has raised $250,000 so far.

The charity, which was created after the Sept. 11 terror attacks, said the sum is about a third of what is needed to pay the home mortgages for the families of Rafael Ramos and Wenjian Liu.

The organization announced earlier this week that it would be taking over the mortgage payments for the two families.

The announcement was made in Staten Island along with former Mayor Rudy Guiliani and Liu’s widow, Pei Xia Chen. Giuliani said he was pledging $20,000 of his own money.

Contributions have been coming in from all over the world, including Hawaii, Italy and the United Kingdom, the foundation said.

In total, the foundation is looking to raise $800,000 to buy the homes of the officers by New Year’s Day.

The Stephen Siller Tunnel to Towers Foundation was created in memory of FDNY firefighter Stephen Siller. On 9/11, Siller abandoned his truck and ran through the Brooklyn-Battery Tunnel with all his gear toward the World Trade Center. He was killed when the South Tower collapsed.

For more information or to donate, visit tunnel2towers.org.

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