Hi...yes its a must for anybody who is applying for a US visa to get police clearance from the country you used to stay for more than 6 months ( whether you stayed for work, studying, visit etc)...you should get one from Oman and it takes time to obtain one...(depending on the country) normally it takes 2- 4 months to get one.
i guess you should start getting information on how to get one from Oman while waiting for your NOA2...see if it possible to apply from their embassy in India.
I applied for Malaysia,Thai,Japan and China...
goodluck to you and hope this helps a bit.
God bless!
lhais got a reaction from Lorily0310 in Foreign Police Certificate