What happened to the people who came out of the graves in Matthew 27:52-53?

These people were saints unto God, meaning that they were saved before Jesus died on the cross but did not have their sins paid for yet.  Before Jesus died to pay for their sins they went to Abraham’s bosom (Luke 16:19-31).  After Jesus’ resurrection these saints rose with Him.  Note verse 53 says “after his resurrection.”  Matthew states that this happened after Jesus’ resurrection, and it had to be because Jesus was the firstborn from the dead (Colossians 1:18).  After many, not all, rose they walked into Jerusalem and many people saw them (v. 53).  We do not know how long they were in the city but eventually they would have been taken on to Heaven since their sins were finally paid for by Jesus.