A 26-year-old man is in the hands of immigration officials after police arrested him on the A16 in Crowland on suspicion of entering the UK illegally.
The man from Iran was arrested at about 6pm on Saturday and he has been detained while Home Office Immigration Enforcement officers deal with his case.
A Home Office spokesman said: “We work closely with the police to tackle illegal immigration and continue to strengthen the security of our borders to stop those who have no right to enter the UK.
“If people have a genuine need of protection they should claim asylum in the first safe country they reach.
“But If they are just seeking to evade immigration control they need to know that they are risking their lives and will get caught.
“The new Immigration Act makes it harder for people to live in the UK illegally and for them to abuse our benefits and public services.
“However, it makes it easier for us to remove them by reducing the number of appeals and anyone found to have no legal right to remain in the UK faces removal.”