Unable to resolve dependencies from the mirror repository for a proxy environment

Hello, We have a proxy environment for the build servers and had setup a Nexus artifacts repository for the Maven Central. All the other dependencies are resolved without issues and downloaded from the mirror except for the below issue which happens only in the build environment, not sure why it is looking at the maven central instead of the mirror.

Here is the error output: http://pastebin.com/G8GNwbr6

Please suggest

Thanks!