Laurel Wamsley

Updated 6 a.m. ET Sunday

A sudden avalanche of mud and water tore through the Colombian city of Mocoa overnight Friday night, killing scores of people while they slept. At least 193 people were killed, according to President Juan Manuel Santos. The Colombian Red Cross reported Saturday that 220 people are missing, and 400 were injured in the disaster.

Since 2010, the default avatar on Twitter has been an egg. The idea apparently was that a new user was like a gestating bird, soon to make its first tweet. It was designed to be playful and cute.

But over time, Twitter's eggs came to symbolize something different: users who remain shadowy on purpose, to harass their fellow tweeters.

Today, Twitter announced that it was doing away with the egg as its default avatar, opting instead for a nondescript person-shape figure. No more bright colors, either — the new avatar is all gray.

A former nurse's aide convicted of killing more three dozen people died on Thursday, two days after he was attacked and beaten in his Ohio prison cell.

As Ohio Public Radio's Karen Kasler reports, "64-year-old Donald Harvey had been nicknamed the 'Angel of Death' in 1987, after admitting to killing 37 elderly or chronically ill people in hospitals in Cincinnati and rural Kentucky beginning in 1970. But after his conviction, he claimed that he had killed up to 50 people."

Thirteen members of a church choir were killed when their bus collided head-on with a pickup truck Wednesday afternoon in Texas. The crash happened about 75 miles west of San Antonio, outside Garner State Park in Uvalde County.

Chinese President Xi Jinping will meet with President Trump next week, a senior State Department official said Tuesday.

This visit will be the first in-person meeting between Trump and Xi, after Trump's sharp criticisms of China during the presidential campaign.

Trump and Xi are likely to get together at Trump's Mar-A-Lago resort, though the White House hasn't officially announced the visit. Likely topics for discussion are Trump's threats to counter China's trade policies, which he has called unfair.

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