A senior investigating officer in the case for West Midlands Police said they are disappointed with the length of the sentences.
Detective Inspector Sharon Naughton said they had been expecting longer.
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Fine and dry with good spells of sunshine this weekend.
Dry and rather warm in sunny spells on Friday.
Police have named a man who died after a knife attack in the St Ann's area of Nottingham as 21-year-old Reuben Morris-Laing.