Is index creating a blocking operation in Mysql Aurora 5.6

We need to create an index in a table which has 53mln records. We don't know how much this operation may be executed.
In our case table can't be locked because it crashes application which can not take a place.

I want to execute this SQL: CREATE INDEX test_idx ON table_name(column(1), column2);
We are using: 5.6.mysql_autora.1.23.2 version

The question is: Will this SQL blocked read&write operations?