A Brooklyn man attacked and tried to sexually assault his 88-year-old neighbor after she let him into his home on Wednesday afternoon, law-enforcement sources told The Post.

After the attack, the woman alerted authorities by hitting her Life Alert button, the sources said.

The elderly woman let the 24-year-old suspect into her home on Vermont Street in East New York at about 2 p.m., police sources said.

Once inside, he punched her in the face and dragged her to the basement, where he attacked her, police sources said.

He eventually ran off, but was busted soon after the attack near Livonia Avenue and Sheffield Avenue, cops said.

Charges against him are pending, cops said.

The woman was being treated at a nearby hospital, cops said. Detectives from the NYPD’s Special Victims Division were investigating the attack, sources said.