SALT LAKE CITY — A man who police say was behind the wheel of a car that struck and killed a pregnant woman in Salt Lake City has been formally charged.

Jack Keith Archibald, 54, is charged with two counts of automobile homicide, a second-degree felony. He is also charged with driving under the influence, failure to stop at a serious injury accident, and leaving the scene of an accident involving death. Further charges include failure to operate a vehicle on the right side of the roadway, and driving on the sidewalk.

Charging documents state that Archibald was driving east on 1700 South near 900 East in Salt Lake City when he swerved into oncoming traffic, and then off the road where he hit a pregnant woman and her young son who were walking on a sidewalk.

Police said Archibald got back into his car and fled. He reportedly parked the damaged car at his workplace and then hid in a shed about half a block away. He was apprehended by police after they said he peeked out of and then left the shed.

Emergency officials performed life-saving measures on the pregnant woman who had been hit, but she died in transit on the way to a hospital.  She was later identified as 23-year-old Libbie Isabel Allan.

The child was hospitalized in critical condition.

Charging documents say that Archibald admitted to having consumed alcohol and marijuana. Police later said that his blood alcohol level registered at 0.136, and later at 0.108. Both were more than twice Utah’s legal blood alcohol level of .05.