Inner join query with array in result field

There 2 tables in my tables

1. contacts (Fields : firstname, lastname, id)
2. phone numbers (Fields : number, id, contact_id)

The result i am looking for is as below.

Firsname Lastname Phone numbers

XYZ ABC Array of numbers

I tried inner join query but it shows me separate result for same contact_id. I tried to use group_by but no luck.