CAMBRIDGE, Mass. (AP) — Two Harvard University freshmen have launched a website designed to connect people fleeing Ukraine to those in safer countries willing to take them in — and it’s generating offers of help and housing worldwide.

Moved by the plight of Ukrainian refugees desperate to escape Russian bombardment across the former Soviet republic, Marco Burstein, 18, of Los Angeles, and Avi Schiffmann, 19, of Seattle, used their coding skills to create UkraineTakeShelter.com over three frenzied days in early March.

Since then, more than 18,000 prospective hosts have signed up on the site to offer assistance to refugees seeking matches with hosts in their preferred or convenient locations. On a recent day,…