The family of a young man who went on a deadly shooting rampage in two Colorado religious centres before killing himself said they were "groping for answers" and praying for the victims' families.

The gunman believed to have killed four people at a Colorado megachurch and a missionary training school had been thrown out of the centre a few years ago and was sending it hate mail, police said.

A US woman has given birth to quintuplets at a Seattle hospital – and now the drive is on to build the family a bigger house.