A Surrey Police spokesman said: "Our searches are currently focused along the river area of Horley and we are keeping an open mind on her whereabouts.
"Surrey Search and Rescue as well as drones and specially trained search officers are continuing to support the search.
"Maria is described as 5ft 3 tall and of average build with black-grey hair. She was last seen wearing a peach coloured, short-sleeved T-shirt, and dark shorts which may have a leopard print design. Maria was also last seen wearing pale pink slip on slippers.
"We are asking anyone who has seen Maria or has any further information on her whereabouts to contact us immediately."
East Surrey Inspector Simon McCarthy said: “We would like to thank all the members of the public who have already come forward with information and offers to help with the search. Although we really appreciate people offering to help, our searches are carried out in a coordinated way and led by specially trained search officers. We are continuing to do all we can to find Maria and would urge anyone who has not already done so to come forward with any information, no matter how insignificant it might seem, as a matter of urgency.”
If you have any other information which could help, please contact Surrey Police quoting crime reference number PR/P21142370 via: Webchat on our website surrey.police.uk or Calling 101