No support in fireplace? Help!

[Fireplaceworries]

Hello,

We are partway through our renovation and removed the gas fire the previous owners installed. It’s left us with a small gap, but we would like to open up the fireplace more, but it seems like there’s no lintel or supportive arched bricks.

Please could someone advise?

Photo attached from the inside of the fireplace.

Thank you,

 

[23vc]

You’d normally put a lintel in, when you open it up.