Yes, God loves even your uncle, in spite of his rebellion and the act he committed. No one is beyond God's love, no matter what they have done: "For God so loved the world that he gave his one and only Son, that whoever believes in him shall not perish but have eternal life" (John 3:16).
This doesn't mean, however, that God overlooks our sins or ignores what we do. Sin is serious; it is so serious that it sent Jesus Christ to the cross. And what your uncle did by murdering someone was especially serious, for life is sacred, and God's Word is very clear: "You shall not murder" (Exodus 20:13). Unless he repents and turns to Christ, he must pay the ultimate, eternal price for his rebellion—which is Hell.
But God still loves your uncle (just as He loves the whole human race), and He stands ready to forgive him and welcome him into His family if he will repent to open his heart to Christ. Do you remember the Apostle Paul? At one time, he hated Jesus and wanted to wipe Christians off the face of the earth. But then he met Jesus, and God forgave Paul and gave him a new heart. The same can happen to anyone who truly repents and turns to Christ.
Pray for your uncle, that God would break his pride and cause him to turn to Christ. And make sure of your own relationship to God. Have you responded to His love by giving your life to Jesus?