Houston places 2.2m people under boil water notice after plant power outage

Residents in largest city in Texas express anger at alert which came hours after power outage at purification facility on Sunday night

The 2.2 million people in Texas's largest city - and the US's fourth most populous - have been placed under a boil water notice since Sunday night, after a power outage caused water pressure to drop at a purification facility earlier in the day.

Some residents expressed anger at being alerted of water safety issues several hours after the outage while others complained about finding out through social media. Officials are testing whether the outage at the facility let bacteria contaminate the local drinking water supply, and results are not immediate.