We hit panic button on accident alarm started going off had difficulty getting it to stop. Car won't start now. Disabled battery and when we hook it back up alarm goes on again. Tell me what to do

There are couple ways you can try to shut it off, not sure if you have done these already, works for most japanese car:
- when the alarm goes on:
1) press and hold the panic button for 5 sec, or
2) press and hold the unlock button
3) insert key to lock or unlock couple times without using the remote keyless this time

make sure all doors are closed while trying the above. hope this helps...good luck