Susan Collins and other Republicans open to allowing witnesses in impeachment trial, a key sticking point in impasse between House and Senate

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1.25am GMT

Kari Paul here, logging off for the weekend! Here is a summary of the key events of the last few hours:

12.53am GMT

Two parents whose children were separated from them as a result of the Trump administration’s “zero tolerance” border policies are suing the federal government for $12m, claiming the children were subject to abuse and neglect while in federal custody.

“The United States government tore these families apart pursuant to a cruel and unconstitutional policy: The government intended to inflict terror and harm on these small children and their fathers, as a means of deterring others from seeking to enter the United States”, said the lawsuit, which was filed Friday in U.S. District Court of Arizona.

According to the lawsuit, the fathers were separated from their children for more than two months, and the federal government gave little, if any, information regarding the location and safety of the children.

The families “suffered, and continue to suffer, physical, mental, and emotional harm,” the lawsuit states. More than a year after they were reunited, the lawsuit says the children exhibit symptoms of post-traumatic stress disorder.