Shadow Communities Secretary Steve Reed admits that Labour losing Hartlepool to the Conservatives is a "shattering blow".
"All of us are devasted to see this happen", the Labour MP said.
Conservative candidate Jill Mortimer defeated Labour's Dr Paul Williams by 6,940 votes in the by-election.
Mr Reed acknowledged that the Labour Party "still have an electoral mountain to climb" following the 2019 General Election.
Report by Thomasl.
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