SAN JUAN, Puerto Rico (AP) — Crews are working to restore power to Puerto Rico after a blackout across the entire island that affected the main airport, several hospitals and hotels filled with Easter vacationers. The blackout left 1.4 million customers without electricity and 328,000 without water. About 12% had power back at the end of the day Wednesday. The blackout snarled traffic, forced businesses to close and left those unable to afford generators scrambling to buy ice and candles. It’s the second islandwide blackout in less than four months. The cause wasn’t yet known, but Puerto Rico has had chronic outages due to hurricane damage and a lack of maintenance and investment in its power grid.