Slow-walking peacocks disrupt busy expressway in US after zoo escape

Slow-walking peacocks disrupted traffic on an expressway in the US, after making an escape from a nearby zoo. 

The four peacocks caused two lanes of the Pennsylvania motorway to close today, reported NBC 10, after the birds broke out of the Philadelphia Zoo.

Aerial footage shows the peacocks walking on one lane of the road.

Police formed a barricade to catch the peacocks, however they flew into trees or across the highway, according to NBC 10. 

Philadelphia Zoo said in a statement to news outlet CBS: "The zoo is home to a free-roaming peacock flock that lives on zoo grounds and is cared for by the zoo's animal and veterinary staff."

"The peacocks do sometimes venture past the zoo's gates and typically return home on their own."

The zoo is intending to locate the peacocks in the morning.