Harare – Zimbabwean Vice President Emmerson Mnangagwa was on Saturday reportedly rushed to hospital after he started vomiting while attending President Robert Mugabe's rally in Gwanda, reports said on Sunday.According to New Zimbabwe.com, unverified sources claimed that the embattled deputy president was poisoned, adding that he suffered an "adverse reaction after drinking a milkshake served at the event". Mnangagwa reportedly walked to the ambulance barely a few minutes after he had vomited during Mugabe's address. "The vice president walked off stage some 45 minutes into Mugabe's address and got into an ambulance amid claims that he was vomiting," the report said.A report by the Standard said the vice president was in a "bad shape". Mnangagwa was escorted to the ambulance by a senior government minister, who reportedly denied knowing anything about Mnangagwa's illness, the report said."I know nothing, who told you that I know anything? I am sorry I don’t know anything like that," the Minister of State Security Kembo Mohadi was quoted as saying. Mnangagwa reportedly offered to resign last week over what he called repeated "public humiliation" by Mugabe's wife Grace. The sources said that Mnangagwa believed there was a plot against him by the system to kick him out.The First Lady had previously told Zimbabwe's vice presidents - Mnangangwa and Phelekezela Mphoko - at a campaign rally in Chinhoyi that they were serving at her husband's will. Grace warned the two deputies that they risked losing their jobs if they did not perform to the expectations of her husband.A few days earlier, the First lady had publicly urged her ageing husband to name his successor.