Hundreds of Nigerians marched on Monday to protest poverty and corruption as President Muhammadu Buhari's prolonged absence abroad for medical tests raises political and economic tensions.

“Nigerians are frustrated and tired with this absentee government,” activist Omoyele Sowore said as he marched in Lagos, Nigeria's largest city. Protesters carried placards saying: “Unemployed people hungry and angry.”

Prices of food and other goods have soared as Nigeria confronts low international prices for oil on which the government depends and a devalued naira currency because of massive foreign currency shortages.

Turnout was small in Lagos, a city of 20 million people, with just dozens turning out in Abuja, the capital. The protest initially was proposed on social media by hip-hop musician 2Face Tubaba Idibia but he tried to call it off after police said they could not guarantee the safety of marchers.

Still, hundreds turned out, rallying around the hashtag #IStandWithNigeria. One protester shouted that Nigeria's expensive government system has turned democracy into “government by the rich, for the rich, to make laws so that poor people suffer”.

Buhari’s campaign to fight the endemic corruption that impoverishes most Nigerians has not achieved any successful high-profile prosecutions though scores of former and current officials have been detained.

Much of the hope engendered by Buhari’s election in 2015 that overturned a sitting president by unifying the opposition has dissipated. Africa's biggest economy has slumped into recession and analysts say the government appears to have no plan to reinvigorate economic growth.

Buhari was supposed to return Monday from a two-week vacation in London. But a statement said he was extending his absence to complete unspecified medical tests. UK-based Songhai Advisory risk analysis said the indefinite extension fuels suspicions about the 74-year-old leader's capacity to govern and increases political and economic uncertainty.

Nigeria confronted months of political paralysis in 2009 when then-President Umaru Yar'Adua went to Saudi Arabia for medical treatment and returned home to die. Politicians from the mainly Muslim north of the country tried to block a Christian vice president from the south from governing in his absence. Already, Songhai Advisory notes, northern Muslims like Buhari are rallying opposition to the possibility that the current Christian vice president would assume Buhari's powers.