Ikrimah bin Khalid said: Some riders gathered on the road, and a previously married woman among them placed her matter in the hands of a man other than her guardian so that he would marry her off, and he married her off. When Sayyiduna Umar (may Allah be pleased with him) learned of this incident, he had both of them flogged and declared the marriage rejected.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب النكاح / 13639