A cyclist has died after being hit by a train at a crossing in Brisbane’s south.

The 69-year-old man was struck while riding his bike on a level train crossing at the corner of Nathan Rd and Penarth St in Runcorn about 4.30am on Monday.

Paramedics rushed to the scene and treated the man for significant life-threatening injures, they said.

Police confirmed the man suffered critical head injuries and was declared dead a short time later.

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Delays to services are expected, with police also warning of traffic delays in the area.

Investigations are continuing.