LibreOffice.app danificado?

After upgrading to LibreOffice 5.0.3 for Mac OS X x86_64 I cannot open the app. I get the message “LibreOffice is damaged and cannot be opened. You should move it to the trash bin”. What is going on?
I have an iMac operating OS X El Capitan v. 10.11.1.
Please advise. Thank you.