Tenant keeps removing smoke alarms and had a fire...

Possession - Section 8 and Section 21

My tenant keeps removing smoke alarm and has had a fire.
In August 2020, I visited the property to carry out a general repair. I noticed that the smoke alarm in the living room had been removed. It is a hard-wired type and it had been removed from its base.
Tenant told me it keeps going off. I fitted a new one, same type and just connected it to the original base. I informed the tenant the importance and safety requirement and my responsibility that I must provide working smoke alarms.
In March 2021, I received a text from the tenant saying she had a fire in the bathroom and the radiator was damaged. I found that the towel rail, bath, landing smoke alarm and ceiling vent had been damaged by the heat and had warped. I had also noticed that the smoke alarm I had replaced in the lounge back in August had again been removed and she had thrown it away because she claimed it keeps going off. It is far enough away from the kitchen so it would not be caused by nuisance false alarms from cooking etc. I have again fitted a new alarm, a 10 year non replaceable battery type and installed it on the other side of the lounge. I have had to replace the bath and radiator and two smoke alarms which she has agreed to pay for.
Five days following the fire, she had a break in. A crowbar was used to gain entry splitting the door, so I had to have this replaced. (I suspect that the fire and break in are linked but that is another story). The repairs have cost me just short of £1000 in less than a week.
She has three children live with her and if the fire had been worse or in the event of another one was to start, and no smoke alarms were fitted then the authorities would come knocking on my door.
I know she is mixing with some bad people and has become a liability and I am issuing a section 21 but currently this is six months wait in which time I could be left with a pile of cinders and risk being prosecuted for not having smoke alarms fitted.
In the interim I have taken photos of the smoke alarms that I have fitted and will make more regular inspections, but this is not enough for me as I have a property ‘at risk’.

She is upto date with her rent and I’ve no evidence of any anti-social behaviour.
Is there any process under section 8 I could use for interfering with mandatory safety equipment?
Any advice welcome.

Thanks inadvance
Kevin