Portland, Ore. ? As Linda and Thom Martin cruised through desolate eastern Oregon, something about the gray van in front of them on Interstate 84 clicked.

“We see this van, we saw it at the same time, and we said, ‘Oh, is that it? Is that the number?”‘ said Linda Martin, 58.

At the wheel was Edward Morris, who had eluded police for two weeks before he was captured Saturday and charged with killing his pregnant wife and three children along a snowy side road in the Tillamook State Forest.

Linda Martin had paid close attention to the case; her grandson had played on a soccer team with the oldest of the slain children.

The Martins thought they spotted Morris about noon Saturday and started following the van. When he pulled in at a gas station in Durkee, Thom Martin, 50, got a look at the man behind the wheel. His head was shaved, but it looked like pictures of Morris that Martin had seen on television.

The Martins followed the van about 20 miles to Baker City, where Morris then drove into a drug store parking lot, and the Martin siblings called 911.

When he came out, the police were waiting.

Prosecutors had already charged Morris with murder in the slayings of his family. He was cooperative in the arrest, authorities said.

The bodies of Morris’ wife, Renee, 31, and their children, Bryant, 10, Alexis, 8 and Jonathan, 4, were found by hunters Dec. 21. Police say the mother and children apparently were killed the day before, but they have yet to reveal how.

Linda and Thom Martin chat after Edward Morris was arrested in Baker City, Ore. The sister and brother spotted Morris' van and called police. Morris was wanted in connection with the deaths of his pregnant wife and three children.

Morris was held overnight in the Baker County Jail. Tillamook County Sheriff Todd Anderson said he was returned to the county jail in Tillamook by private plane early Sunday afternoon and would be arraigned today.

Authorities had offered a $50,000 reward for information leading to Morris’ arrest. The Martins said they had not been told whether they are eligible. Anderson said he thought they would be.

Authorities had said Morris should be considered armed and dangerous, although no weapon was found in his van.

Morris’ father, Paul, who had made public appeals to his son to surrender, was told of the arrest Saturday.

“I’m numb. I don’t know what to say. I don’t know what to do,” Paul Morris said.