CHICAGO (CBS) — Metra commuters taking the BNSF and Southwest Service trains should expect “extensive delays” Friday evening, according to Metra officials.

A train was blocking all tracks out of the yard as of 4 p.m., a tweet by Metra stated. It was moved by 4:46 p.m., officials said in an update.

Metra BNSF wrote in a tweet that trains would be back on schedule after 5:11 p.m.

Riders were being asked to take alternative transportation if possible.

Metra began it’s overcrowding prevention plan shortly after 4 p.m.

This is a developing story.