Essex Head Coach Paul Grayson said he was delighted Mahmood had joined the club.
"I like cricketers who feel they have point to prove to people and he has lots of ability, he's experienced and he's a fit guy who can bowl with good pace as well so we feel Saj will be a real addition to the squad."
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Additional police will be on duty this weekend on what is expected to be one of the busiest weekends of the year.
Early cloud and rain will clear to the south and the sun will come out throughout the region. However, it will feel colder than yesterday.
Councils are examining their budgets and deciding where savings and cuts can be made as government funding is to be cut by 14% next year.